Major interaction on record — check this product against your medications before combining. Based on 7 of 10 ingredients. Check your meds →
Dietary supplement

Kids' Sambucus Chewables Ingredients & Drug Interactions

by Nature's Answer

Kids' Sambucus Chewables label
See full label image
Tablet Or Pill Category: Botanical With Nutrients
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Kids' Sambucus Chewables against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Kids' Sambucus Chewables is a dietary supplement by Nature's Answer with 10 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 1,206 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Grapefruit, Vitamin C, Black Currant. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Kids' Sambucus Chewables by Nature's Answer

Ask about any prescription or over-the-counter medication and we check it for interactions with Kids' Sambucus Chewables by Nature's Answer — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Kids' Sambucus Chewables by Nature's Answer

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 4 of its 9 active ingredients.
  • “Proprietary Fruit Blend” is a proprietary blend — the label gives one combined amount (26 mg) without saying how much of each component you get.

Kids' Sambucus Chewables contains 9 ingredients, including vitamin C for immune support, zinc for various metabolic roles, and a proprietary fruit blend. The fruit blend includes black elderberry extract (the product's namesake active ingredient), grapefruit, pear, cherry, pineapple, and black currant.

The remaining ingredients are inactive—maltodextrin, cane sugar, dextrose, stearic acid, natural flavors, malic acid, magnesium stearate, citric acid, mannitol, calcium silicate, and croscarmellose sodium (which serve as sweeteners, binders, or flow agents).

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Vitamin C deficiency — rated "Effective" (Vitamin C) (Natural Medicines).
  • On file: Zinc deficiency — rated "Effective" (Zinc) (Natural Medicines).
  • On file: Wilson disease — rated "Likely Effective" (Zinc) (Natural Medicines).
  • On file: Acne — rated "Possibly Effective" (Zinc) (Natural Medicines).
  • On file: Acrodermatitis enteropathica — rated "Possibly Effective" (Zinc) (Natural Medicines).

In the data we hold, vitamin C is rated Effective for vitamin C deficiency and Possibly Effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections. Zinc is Effective for zinc deficiency and Likely Effective for Wilson disease, and Possibly Effective for acne, age-related macular degeneration, and diabetes.

For the fruit components—grapefruit, pear, black currant, elderberry, and cherry—no effectiveness evidence is established in our data for the conditions often marketed for them (respiratory infections, immune support, etc.).

The evidence, ingredient by ingredient Vitamin C Zinc Grapefruit Pear Sweet Cherry Black Currant Elderberry

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 6 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C at normal supplement doses is well tolerated in children; very high doses can cause abdominal cramps, heartburn, diarrhea, nausea, or kidney stones in those prone to them. Zinc at recommended amounts is well tolerated but can cause metallic taste, nausea, or diarrhea at higher doses.

Grapefruit is safe as food but carries interaction risks (noted above). Elderberry products made from ripe, cooked fruit are well tolerated; raw or unripe berries, seeds, and plant parts can cause nausea, vomiting, severe diarrhea, and neurological symptoms due to cyanogenic glycosides.

Black currant as food is safe; supplements are less studied. Cherry, pear, and the other fruits are generally well tolerated in normal amounts.

For pregnancy and breastfeeding in children's formulations, safety data on the concentrated fruit extracts is limited—discuss with your child's doctor.

Side effects, ingredient by ingredient Vitamin C Zinc Grapefruit Pear Sweet Cherry Black Currant Elderberry

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 5 of the 7 matched ingredients can interact with medications — Elderberry, Grapefruit, Zinc, Vitamin C, Black Currant.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; heart-rhythm medications.
  • For scale: 1,207 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

If your child takes any of these, check with your pharmacist before adding this product: cyclosporine or other immunosuppressants, scopolamine, amiodarone, buspirone, dextromethorphan, estrogens (birth control or hormone therapy), warfarin or other blood thinners, anticoagulant or antiplatelet drugs, chemotherapy drugs, tetracycline or quinolone antibiotics, and HIV medications. No interactions are documented for pineapple or fructooligosaccharide, which we could not check.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

Kids' Sambucus Chewables is a multivitamin and fruit-extract supplement with vitamin C, zinc, and elderberry as its main active ingredients. It has documented interactions with over 1,200 medications across many drug types, especially through grapefruit and vitamin C.

Before starting this product, talk it over with your child's doctor or pharmacist to make sure it won't interfere with any medications they're taking.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 7 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 26, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Kids' Sambucus Chewables, straight from the product label.

Brand Nature's Answer
Barcode (UPC) 083000262678
Net contents 60 Chewable Tablet(s)
Market status On market
Date entered into DSLD Dec 26, 2020
DSLD ID 233027
Product type Botanical With Nutrients
Supplement form Tablet Or Pill
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Children 4 or More Years of Age, Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Kids' Sambucus Chewables by Nature's Answer, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Tablet(s)
Maximum serving Sizes:
1 Tablet(s)
Servings per container
60
UPC/BARCODE
083000262678
IngredientAmount% DV
Calories5 Calorie(s)--
Total Carbohydrates1 Gram(s)1%
Sugar1 Gram(s)--
Vitamin C100 mg111%
Added Sugars1 Gram(s)2%
Zinc5 mg45%
Proprietary Fruit Blend26 mg--
Grapefruit0 NP--
Pear0 NP--
Black Elderberry (Sambucus nigra) fruit extract225 mg--
Cherry0 NP--
Pineapple0 NP--
Black Currant0 NP--
Fructooligosaccharide25 mg--

Other ingredients: Maltodextrin, Cane Sugar, Evaporated, Dextrose, Stearic Acid, Natural flavors, Malic Acid, Magnesium Stearate, Citric Acid, Mannitol, Calcium Silicate, Croscarmellose Sodium

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Discover Nature's Answer and trust the Difference... The True Nature of Our Standards goes way beyond the herb...

Nature’s Answer since 1972

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

Warning: Keep out of reach of children.

Do not use if safety seal is damaged or missing.

If you are pregnant, nursing, taking any medications, planning any medical procedure or have a medical condition, consult with your healthcare practitioner before use.

Storage

Store in a cool, dry place

Formulation

Gluten Free

Supports a Healthy Immune System

Vegan

Gluten-Free

Non GMO Project Verified nongmoproject.org Absolutely no artificial preservatives

Formula

Made From 7,200 mg Black Elderberries per serving Black Elderberry + Vitamin-C and Zinc

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, chew 1 tablet. Children 4-13 years old, repeat as necessary up to 3 (three) times per day. Do not exceed more than 9 (nine) tables per day. Adults 14 years and older, repeat as necessary up to 4 (four) times per day. Do not exceed 12 (twelve) tablets per day.

Brand IP Statement(s)

Copyright 2019 Nature's Answer, Inc.

Seals/Symbols

Non GMO Project Verified nongmoproject.org

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Kids' Sambucus Chewables by Nature's Answer label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Kids' Sambucus Chewables label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Kids' Sambucus Chewables by Nature's Answer

These are the 10 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Sugar

1 Gram(s) per serving

Vitamin C

Interacts with
207 drugs
100 mg per serving Form: Ascorbic Acid

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Zinc

Interacts with
67 drugs
5 mg per serving Form: Zinc Citrate

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but suppleme...

Zinc monograph & interactions

Proprietary Fruit Blend

26 mg per serving

Black Elderberry (Sambucus nigra) fruit extract

Interacts with
121 drugs
225 mg per serving Form: Anthocyanins

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu sym...

Black Elderberry (Sambucus nigra) fruit extract monograph & interactions

Fructooligosaccharide

25 mg per serving Form: Inulin

Other (inactive) ingredients: Maltodextrin, Cane Sugar, Evaporated, Dextrose, Stearic Acid, Natural flavors, Malic Acid, Magnesium Stearate, Citric Acid, Mannitol, Calcium Silicate, Croscarmellose Sodium. These complete the product’s ingredient list but are not active constituents.

Interaction report

Kids' Sambucus Chewables by Nature's Answer Drug Interactions

Want to check YOUR meds against Kids' Sambucus Chewables?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,206Drugs
776 Major 385 Moderate 45 Minor

Ingredients driving the most interactions

Grapefruit 990
Vitamin C 207
Black Currant 140
Black Elderberry (Sambucus nigra) fruit extract 121
Zinc 67

Individual Drug Interactions

The ingredients in Kids' Sambucus Chewables interact with 1,206 drugs. Click any drug to see the details.

5 of the 10 ingredients in Kids' Sambucus Chewables interact with drugs. Each result below shows which ingredient is responsible. Grapefruit Vitamin C Black Currant Black Elderberry (Sambucus nigra) fruit extract Zinc

Each ingredient & the kinds of drugs it affects

For each ingredient in Kids' Sambucus Chewables with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Grapefruit62 drug types · 990 drugs

Amiodarone (Cordarone)

Grapefruit juice can increase blood levels of amiodarone, potentially increasing the effects and adverse effects of amiodarone.
Clinical research shows that grapefruit juice inhibits metabolism and increases absorption of amiodarone. Grapefruit juice increases amiodarone plasma levels by 50% and peak concentration by 84%.

Likelihood Probable Evidence B
Artemether (Artenam, Paluther)

Grapefruit juice can increase blood levels of oral artemether, potentially increasing the effects and adverse effects of artemether.
Clinical research shows that grapefruit juice increases the levels of oral artemether by 90% to 250% in healthy males.

Likelihood Likely Evidence B
Benzodiazepines

Grapefruit juice might increase blood levels of some oral benzodiazepines, potentially increasing the effects and adverse effects of these drugs.
Clinical research shows that grapefruit juice can increase plasma triazolam concentrations. Repeated consumption of grapefruit juice greatly increases triazolam concentrations and prolongs the half-life, probably due to inhibition of cytochrome P450 3A4 (CYP3A4). Some studies show that grapefruit juice, particularly when taken in large quantities, reduces the clearance and increases the maximum blood levels, area under the plasma concentration curve (AUC), and duration of effect of midazolam. However, there is no effect on intravenous midazolam. Grapefruit juice has also been shown to increase the maximum blood levels and duration of effect of diazepam, but the clinical significance of this is not known. This interaction does not appear to occur with alprazolam.

Likelihood Likely Evidence B
Buspirone (Buspar)

Grapefruit juice can increase blood levels of buspirone, potentially increasing the effects and adverse effects of buspirone.
Clinical research shows that grapefruit juice increases absorption and plasma concentrations of buspirone.

Likelihood Likely Evidence B
Calcium Channel Blockers

Grapefruit juice can increase blood levels of oral calcium channel blockers, potentially increasing the effects and adverse effects of these drugs.
Clinical research shows that grapefruit juice increases absorption and plasma concentrations of amlodipine, nifedipine, nisoldipine, verapamil, felodipine, nimodipine, nicardipine, diltiazem, pranidipine, nitrendipine, and manidipine, This interaction is likely the result of the inhibition of intestinal metabolism of these drugs by CYP3A4, although some research suggests grapefruit may alter plasma drug levels by reducing the rate of gastric emptying. Consuming grapefruit juice 1 liter daily increases steady state concentrations of verapamil by as much as 50%. However, some references dispute the clinical relevance of the interactions with amlodipine, diltiazem, and verapamil. Other research in healthy individuals suggests plasma levels of felodipine and nifedipine are not affected when given intravenously. There is considerable interindividual variability in the effect of grapefruit juice on drug metabolism, which might account for inconsistent study results. In healthy older adults, the hemodynamic response to felodipine plus grapefruit juice might be influenced by altered autonomic regulation. In older healthy adults, a single dose of grapefruit juice and felodipine enhanced the blood pressure-lowering effects of felodipine. However, after a week of grapefruit juice and felodipine (steady state), the hypotensive activity was reduced, possibly due to compensatory tachycardia. Research indicates it is necessary to withhold grapefruit juice for as long as 3 days to avoid interactions with felodipine and nisoldipine.

Likelihood Likely Evidence B
Carbamazepine (Tegretol)

Grapefruit juice can increase blood levels of carbamazepine, potentially increasing the effects and adverse effects of carbamazepine.
Clinical research shows that grapefruit juice increases absorption and plasma concentrations of carbamazepine.

Likelihood Likely Evidence B
Carvedilol (Coreg)

Grapefruit juice can increase blood levels of carvedilol, potentially increasing the effects and adverse effects of carvedilol.
Clinical research shows that grapefruit juice increases the bioavailability of a single dose of carvedilol by 16%.

Likelihood Likely Evidence B
Celiprolol (Celicard)

Grapefruit juice can decrease blood levels of celiprolol, potentially decreasing the clinical effects of celiprolol.
In human research, taking grapefruit juice within two hours of celiprolol appears to decrease absorption and blood levels of celiprolol by approximately 85%. This interaction is due to grapefruit-induced inhibition of organic anion transporting polypeptide (OATP). Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction.

Likelihood Probable Evidence B
Cisapride (Propulsid)

Grapefruit juice can increase blood levels of cisapride, potentially increasing the effects and adverse effects of cisapride.
Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of cisapride. According to the cisapride prescribing information, grapefruit juice is contraindicated in patients taking cisapride.

Likelihood Likely Evidence B
Clomipramine (Anafranil)

Theoretically, grapefruit juice might increase blood levels of clomipramine, potentially increasing the effects and adverse effects of clomipramine.
Case reports have shown that clomipramine trough levels increase significantly after the addition of grapefruit juice to the therapeutic regimen.

Likelihood Probable Evidence D
Clopidogrel (Plavix)

Grapefruit juice can decrease blood levels of the active metabolite of clopidogrel, thereby decreasing the antiplatelet effect of clopidogrel.
Clopidogrel is an antiplatelet prodrug that is metabolized primarily by cytochrome P450 2C19 (CYP2C19) to form the active metabolite. A small clinical study shows that taking grapefruit juice with clopidogrel decreases plasma levels of the active metabolite by more than 80% and impairs the antiplatelet effect of clopidogrel. This effect is possibly due to grapefruit-induced inhibition of CYP2C19.

Likelihood Probable Evidence B
Cyclosporine (Neoral, Sandimmune)

Grapefruit juice can increase blood levels of oral cyclosporine, potentially increasing the effects and adverse effects of cyclosporine.
Clinical research shows that grapefruit juice increases the absorption and plasma concentrations of cyclosporine. The mechanism of action is unclear. However, there is no effect on intravenous cyclosporine.

Likelihood Likely Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Grapefruit juice can increase levels of drugs metabolized by CYP3A4.
Clinical research shows that grapefruit juice can inhibit CYP3A4 metabolism of drugs, causing increased drug levels and potentially increasing the risk of adverse effects. When taken orally, effects of grapefruit juice on CYP3A4 levels appear to last at least 48 hours. Grapefruit's ability to inhibit CYP3A4 has even been harnessed to intentionally increase levels of venetoclax, which is metabolized by CYP3A4, in an elderly patient with acute myeloid leukemia who could not afford full dose venetoclax. The lower dose of venetoclax in combination with grapefruit juice resulted in serum levels of venetoclax in the therapeutic reference range of full dose venetoclax and positive treatment outcomes for the patient.
Professional consensus recommends the consideration of patient age, existing medical conditions, additional medications, and the potential for additive adverse effects when evaluating the risks of concomitant use of grapefruit juice with any medication metabolized by CYP3A4. While all patients are at risk for interactions with grapefruit juice consumption, patients older than 70 years of age and those taking multiple medications are at the greatest risk for a serious or fatal interaction with grapefruit juice.

Likelihood Likely Evidence B
Dextromethorphan (Robitussin Dm, Others)

Grapefruit juice can increase blood levels of dextromethorphan, potentially increasing the effects and adverse effects of dextromethorphan.
Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism, causing increased dextromethorphan levels.

Likelihood Probable Evidence B
Estrogens

Grapefruit juice can increase blood levels of estrogens, potentially increasing the effects and adverse effects of estrogens.
Clinical research shows that grapefruit increases the levels of endogenous and exogenous estrogens by inhibiting cytochrome P450 3A4 (CYP3A4) enzymes. Grapefruit juice increases exogenously administered 17-beta-estradiol by about 20% in females without ovaries and ethinyl-estradiol in healthy females.

Likelihood Probable Evidence B
Etoposide (Vepesid)

Grapefruit juice can decrease blood levels of etoposide, potentially decreasing the clinical effects of etoposide.
Clinical research shows that grapefruit juice decreases the absorption and plasma concentrations of etoposide. There is some evidence that grapefruit juice co-administered with oral etoposide can reduce levels of etoposide by about 26%. Grapefruit juice seems to inhibit organic anion transporting polypeptide (OATP), which is a drug transporter in the gut, liver, and kidney. Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction.

Likelihood Probable Evidence B
Halofantrine

Grapefruit juice can increase blood levels of halofantrine, potentially increasing the effects and adverse effects of halofantrine.
Clinical research shows that grapefruit juice inhibits cytochrome P450 3A4 (CYP3A4) metabolism, which increases halofantrine levels and peak concentration, as well as a marker of ventricular tachyarrhythmia potential.

Likelihood Probable Evidence B
Hmg-Coa Reductase Inhibitors ("Statins")

Grapefruit juice can increase blood levels of statins that are metabolized by cytochrome P450 3A4 (CYP3A4), potentially increasing the effects and adverse effects of these statins. Additionally, grapefruit juice might interfere with the bioavailability of statins that are substrates of organic anion transporting polypeptides (OATP).
Clinical research shows that grapefruit juice inhibits metabolism and increases absorption and plasma concentrations of statins that are metabolized by CYP3A4. These include lovastatin, simvastatin, and atorvastatin. Keep in mind that there is considerable variability in the effect of grapefruit juice on drug metabolism, so individual patient response is difficult to predict.
Some statins, including pravastatin, fluvastatin, pitavastatin, and rosuvastatin, are not metabolized by CYP3A4. However, grapefruit juice might still affect the bioavailability of these statins. These statins are substrates of OATP. Grapefruit juice can inhibit OATP. Therefore, grapefruit juice may reduce the bioavailability or increase drug levels of these statins depending on the type of OATP. However, grapefruit juice affects OATP for only a short time. Therefore, separating drug administration by at least 4 hours is likely to avoid this interaction.

Likelihood Likely Evidence B
Methadone (Dolophine)

Grapefruit juice can increase blood levels of methadone, potentially increasing the effects and adverse effects of methadone.
Clinical research shows that grapefruit juice inhibits the metabolism of methadone, increasing methadone levels and peak concentrations. In one case, a 51-year-old male taking methadone 90 mg daily and no other medications was found unresponsive. The patient reported drinking grapefruit juice 500 mL daily for 3 days prior to the event. Methadone is a substrate of cytochrome P450 3A4 (CYP3A4), and grapefruit juice-induced inhibition of CYP3A4 is the likely cause of this interaction.

Likelihood Probable Evidence B
Methylprednisolone

Grapefruit juice can increase blood levels of methylprednisolone, potentially increasing the effects and adverse effects of methylprednisolone.
Clinical research shows that grapefruit juice can increase the plasma concentration of orally administered methylprednisolone. Grapefruit juice 200 mL three times daily given with methylprednisolone 16 mg increased methylprednisolone half-life by 35%, peak plasma concentration by 27%, and total area under the curve by 75%.

Likelihood Likely Evidence B
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Grapefruit juice can decrease levels of drugs that are substrates of OATP.
In vitro and clinical research show that consuming grapefruit juice inhibits OATP, which reduces the bioavailability of oral drugs that are substrates of OATP. Various clinical studies have shown reduced absorption of OATP substrates when taken with grapefruit, including fexofenadine, acebutolol, aliskiren, celiprolol, levothyroxine, nadolol, and pitavastatin. Grapefruit juice is thought to affect OATP for only a short time. Therefore, separating drug administration and consumption of grapefruit by at least 4 hours is likely to prevent this interaction.

Likelihood Likely Evidence B
Praziquantel (Biltricide)

Grapefruit juice can increase blood levels of praziquantel, potentially increasing the effects and adverse effects of praziquantel.
Clinical research shows that grapefruit juice can inhibit cytochrome P450 3A4 (CYP3A4) metabolism of praziquantel. Plasma concentrations of praziquantel can increase by as much as 160% when administered with 250 mL of commercially available grapefruit juice.

Likelihood Probable Evidence B
Qt Interval-Prolonging Drugs

Grapefruit or grapefruit juice, especially if consumed in large amounts, can cause additive QT interval prolongation when taken with QT interval-prolonging drugs, potentially increasing the risk of ventricular arrhythmias.
Clinical research in healthy volunteers shows that drinking 6 liters of grapefruit juice over 6 hours prolonged the QTc by a peak amount of 14 milliseconds (ms). This prolongation was similar to the QT prolongation caused by the drug moxifloxacin. In individuals with long QT syndrome, a smaller dose of grapefruit juice, 1.5 liters, resulted in a greater peak QTc prolongation of about 30 ms. The effect of smaller quantities of grapefruit juice on the QT interval is unclear.

Likelihood Probable Evidence B
Quetiapine (Seroquel)

Grapefruit juice may increase blood levels of quetiapine, increasing the effects and adverse effects of quetiapine.
Quetiapine is metabolized by cytochrome P450 3A4 (CYP3A4). Grapefruit can inhibit CYP3A4. In one case report, a healthy 28-year-old female with bipolar disorder stabilized on quetiapine 800 mg daily presented with quetiapine toxicity considered to be related to consuming a gallon of grapefruit juice over the past 24 hours.

Likelihood Probable Evidence B
Quinidine

Grapefruit juice can alter blood levels of quinidine, potentially increasing or decreasing the clinical effects of quinidine.
Clinical research shows that grapefruit juice decreases quinidine absorption, clearance, and metabolism, and prolongs the half-life by about 20%.

Likelihood Probable Evidence B
Grapefruit full monograph & all 62 interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions

Black Currant2 drug types · 140 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, black currant seed oil might increase the risk of bleeding if used in combination with anticoagulant or antiplatelet drugs.
Gamma-linolenic acid (GLA), a constituent of black currant seed oil, appears to have antiplatelet effects.

Likelihood Possible Evidence D
Phenothiazines

Theoretically, black currant seed oil might increase the risk of seizure in patients receiving phenothiazines.
Black currant seed oil contains gamma-linolenic acid (GLA). There is some concern that taking supplements containing GLA might cause seizures, or lower the seizure threshold, when taken with phenothiazines, although there is no evidence that black currant seed oil causes seizures. In one report, three patients with schizophrenia who had received phenothiazines developed EEG changes suggestive of temporal lobe epilepsy after starting treatment with GLA, although none experienced an actual seizure. In another report, two patients with schizophrenia who were stabilized on phenothiazines developed seizures when evening primrose 4 grams daily, which contains GLA, was added. One of these patients had a prior history of seizures.

Likelihood Possible Evidence D
Black Currant full monograph & interactions

Black Elderberry (Sambucus nigra) fruit extract2 drug types · 121 drugs

Immunosuppressants

Theoretically, elderberry might interfere with immunosuppressant therapy due to its immunostimulant activity.
Elderberry has immunostimulant activity, increasing the production of cytokines, including interleukin and tumor necrosis factor.

Likelihood Possible Evidence B
Pazopanib (Votrient)

Theoretically, elderberry might interact with pazopanib, potentially increasing the risk of adverse effects.
In one case, a 65-year-old patient taking pazopanib for 4 weeks for soft-tissue sarcoma developed severe nausea, loose stools, and elevated alanine transaminase and aspartate transaminase levels and was diagnosed with grade 3 liver injury. The patient reported taking elderberry supplements for 2 years, dose unspecified, and was also taking a multivitamin and a calcium supplement. The patient's symptoms and liver enzyme levels improved upon discontinuation of pazopanib and all supplements. Pazopanib treatment was re-initiated, at a lower dose, with no further evidence of liver injury. It was unclear in this case report if the elderberry supplements were derived from the berry, the flower, or the combination.

Likelihood Possible Evidence D
Black Elderberry (Sambucus nigra) fruit extract full monograph & interactions

Zinc10 drug types · 67 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Theoretically, zinc might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide should be taken at least 2 hours before or 6 hours after zinc containing products.

Likelihood Probable Evidence D
Cephalexin (Keflex)

Zinc might decrease cephalexin levels by chelating with cephalexin in the gut and preventing its absorption.
A pharmacokinetic study shows that zinc sulfate 250 mg taken concomitantly with cephalexin 500 mg decreases peak levels of cephalexin by 31% and reduces the exposure to cephalexin by 27%. Also, taking zinc sulfate 3 hours before cephalexin decreases peak levels of cephalexin by 11% and reduces the exposure to cephalexin by 18%. By decreasing cephalexin levels, zinc might increase the risk of treatment failure. This effect does not occur when zinc is taken 3 hours after the cephalexin dose. To avoid an interaction, advise patients take zinc sulfate 3 hours after taking cephalexin.

Likelihood Probable Evidence B
Cisplatin (Platinol-Aq)

Theoretically, zinc might interfere with the therapeutic effects of cisplatin.
Animal research suggests that zinc stimulates tumor cell production of the protein metallothionein, which binds and inactivates cisplatin. It is not known whether zinc supplements or high dietary zinc intake can cause clinically significant interference with cisplatin therapy. Cisplatin might also increase zinc excretion.

Likelihood Possible Evidence D
Integrase Inhibitors

Theoretically, taking zinc along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Zinc is a divalent cation. Pharmacokinetic studies have shown that other divalent cations such as calcium and iron can decrease blood levels of the integrase inhibitor dolutegravir through chelation.

Likelihood Possible Evidence D
Penicillamine (Cuprimine, Depen)

Zinc might reduce the levels and clinical effects of penicillamine.
By forming an insoluble complex with penicillamine, zinc interferes with penicillamine absorption and activity. Zinc supplements reduce the efficacy of low-dose penicillamine (0.5-1 gram/day), but do not seem to affect higher doses (1-2.75 gram/day), provided dosing times are separated. Advise patients to take zinc and penicillamine at least 2 hours apart.

Likelihood Probable Evidence B
Quinolone Antibiotics

Zinc can decrease the levels and clinical effects of quinolones antibiotics.
Quinolones form complexes with zinc in the gastrointestinal tract, reducing absorption of both the quinolone and zinc if taken at the same time. Advise patients to take these drugs at least 2 hours before, or 4-6 hours after, zinc supplements.

Likelihood Probable Evidence B
Ritonavir (Norvir)

Zinc modestly reduces levels of ritonavir.
Clinical research shows that zinc might reduce serum ritonavir levels by chelating with ritonavir in the gut and preventing its absorption. In patients with HIV, ritonavir is taken with atazanavir to prevent the metabolism and increase the effects of atazanavir. A pharmacokinetic study shows that, in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate (Solvazinc tablets) 125 mg as a single dose or as multiple daily doses for 2 weeks reduces plasma levels of ritonavir by about 16%. However, atazanavir levels still remains high enough to prevent HIV virus replication. Therefore, the decrease in ritonavir levels is not likely to be clinically significant.

Likelihood Probable Evidence B
Tetracycline Antibiotics

Zinc might reduce levels of tetracycline antibiotics.
Tetracyclines form complexes with zinc in the gastrointestinal tract, which can reduce absorption of both the tetracycline and zinc when taken at the same time. Taking zinc sulfate 200 mg with tetracycline reduces absorption of the antibiotic by 30% to 40%. Demeclocycline and minocycline cause a similar interaction. However, doxycycline does not seem to interact significantly with zinc. Advise patients to take tetracyclines at least 2 hours before, or 4-6 hours after, zinc supplements to avoid any interactions.

Likelihood Probable Evidence B
Amiloride (Midamor)

Amiloride can modestly reduce zinc excretion and increase zinc levels.
Clinical research shows that amiloride can reduce urinary zinc excretion, especially at doses of 10 mg per day or more. This zinc-sparing effect can help to counteract zinc losses caused by thiazide diuretics, but it is unlikely to cause zinc toxicity at usual amiloride doses. The other potassium-sparing diuretics, spironolactone (Aldactone) and triamterene (Dyrenium), do not seem to have a zinc-sparing effect.

Likelihood Probable Evidence B
Atazanavir (Reyataz)

Zinc modestly reduces levels of atazanavir, although this effect does not seem to be clinically significant.
Clinical research shows that zinc might decrease serum atazanavir levels by chelating with atazanavir in the gut and preventing its absorption. Although a single dose of zinc sulfate (Solvazinc tablets) 125 mg orally does not affect atazanavir concentrations in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate 125 mg daily for 2 weeks reduces plasma levels of atazanavir by about 22% in these patients. However, despite this decrease, atazanavir levels still remain at high enough concentrations for the prevention of HIV virus replication.

Likelihood Probable Evidence B
Zinc full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Kids' Sambucus Chewables, from the product label.

Nature's Answer

See all Nature's Answer products
Name
Nature's Answer
Street Address
85 Commerce Drive
City
Hauppauge
State
NY
ZipCode
11788
Phone Number
(800) 439-2324
Web Address
www.naturesanswer.com
Pharmacist Counseling Corner

Kids' Sambucus Chewables by Nature's Answer: Common Questions

Does Kids' Sambucus Chewables by Nature's Answer interact with any medications?
Yes. Based on its ingredients, Kids' Sambucus Chewables has a known interaction with 1,206 medications, including 776 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Kids' Sambucus Chewables contains 10 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is this safe for my kid to take with their antibiotics?
It depends on which antibiotic. Zinc in this product can reduce absorption of tetracycline antibiotics (like doxycycline) and quinolones (like ciprofloxacin), making them less effective. Your child's doctor or pharmacist should confirm whether their specific antibiotic is affected and adjust timing if needed.
Can I give this if my child takes a blood thinner?
Black currant seed oil in this product theoretically increases bleeding risk with anticoagulants and antiplatelets. Vitamin C at high doses can also reduce warfarin effectiveness. Talk with your child's doctor or pharmacist before using it.
Does elderberry actually work for colds or the flu?
In our data, there is insufficient reliable evidence to rate elderberry for respiratory tract infections, coughs, or colds. The effectiveness is not established.
Are there any side effects from the vitamin C or zinc at the doses in this product?
At normal chewable supplement doses, both are well tolerated. Vitamin C can cause mild stomach upset, heartburn, or diarrhea at very high doses. Zinc may cause nausea or a metallic taste but is safe at recommended levels.
Is this okay if my child is on seizure medication?
Black currant seed oil in this product theoretically raises seizure risk when combined with phenothiazines (an older class of psychiatric medication). Check with your child's doctor or pharmacist first.
Why does this contain grapefruit if it interacts with so many drugs?
Grapefruit is included as a flavoring and nutrient source in the fruit blend. The interactions are serious, which is why you need to check with your pharmacist about your child's specific medications before starting this product.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Kids' Sambucus Chewables label
Go deeper

The Full Monographs Behind Kids' Sambucus Chewables’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Zinc

Interacts with 67 drugs

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but supplements can help correct or prevent a defici...

Read the full Zinc monograph → Herb & supplement monograph

Grapefruit

Interacts with 990 drugs

Grapefruit is a nutritious citrus fruit rich in vitamin C and other nutrients, and it is generally safe to eat. However, grapefruit is famous for serious interactions with many prescription...

Read the full Grapefruit monograph → Herb & supplement monograph

Pear

Pear is a common, nutritious fruit that provides fiber, water, vitamin C, and antioxidants, and it is a healthy part of most diets. Beyond its value as a food, evidence for pears as a medici...

Read the full Pear monograph → Herb & supplement monograph

Sweet Cherry

Sweet cherry (Prunus avium) is a popular fruit rich in antioxidants and natural plant pigments, and it is sometimes used as a supplement for gout, sore muscles, and sleep. The research that...

Read the full Sweet Cherry monograph → Herb & supplement monograph

Black Currant

Interacts with 140 drugs

Black currant is a nutritious berry that is rich in vitamin C and antioxidants, and its seed oil contains the omega-6 fatty acid GLA. While it is enjoyed safely as a food and is popular as a...

Read the full Black Currant monograph → Herb & supplement monograph

Elderberry

Interacts with 121 drugs

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu symptoms, but the evidence is limited and n...

Read the full Elderberry monograph →
Sources

Sources & How We Checked

Kids' Sambucus Chewables's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 315 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
  26. Weintraub M, Griner PF. Warfarin and ascorbic acid: lack of evidence for a drug interaction. Toxicol Appl Pharmacol 1974;28:53-6. PubMed
  27. Lee DH, Folsom AR, Harnack L, et al. Does supplemental vitamin C increase cardiovascular disease risk in women with diabetes? Am J Clin Nutr 2004;80:1194-200. PubMed
  28. Taylor EN, Stampfer MJ, Curhan GC. Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up. J Am Soc Nephrol 2004;15:3225-32. PubMed
  29. Ward NC, Hodgson JM, Croft KD, et al. The combination of vitamin C and grape-seed polyphenols increases blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens 2005;23:427-34.. PubMed
  30. Prasad KN. Rationale for using high-dose multiple dietary antioxidants as an adjunct to radiation therapy and chemotherapy. J Nutr 2004;134:3182S-3S. PubMed
  31. Conklin KA. Cancer chemotherapy and antioxidants. J Nutr 2004;134:3201S-3204S. PubMed
  32. Fairweather-Tait S, Hickson K, McGaw B, et al. Orange juice enhances aluminium absorption from antacid preparation. Eur J Clin Nutr. 1994;48(1):71-3.
  33. Gruenwald, J., Graubaum, H. J., Busch, R., and Bentley, C. Safety and tolerance of ester-C compared with regular ascorbic acid. Adv.Ther. 2006;23(1):171-178.
  34. Rahimi, R., Nikfar, S., Rezaie, A., and Abdollahi, M. A meta-analysis on the efficacy and safety of combined vitamin C and E supplementation in preeclamptic women. Hypertens.Pregnancy. 2009;28(4):417-434. PubMed
  35. Einerson, B., Nathorn, C., Kitiyakara, C., Sirada, M., and Thamlikitkul, V. The efficacy of ascorbic acid in suboptimal responsive anemic hemodialysis patients receiving erythropoietin: a meta-analysis. J Med.Assoc.Thai. 2011;94 Suppl 1:S134-S146.
  36. Li, G., Li, L., Yu, C., and Chen, L. Effect of vitamins C and E supplementation on Helicobacter pylori eradication: a meta-analysis. Br.J Nutr 2011;106(11):1632-1637.
  37. Chen X, Shen L, Gu X, et al. High-dose supplementation with vitamin C--induced pediatric urolithiasis: the first case report in a child and literature review. Urology. 2014;84(4):922-4. PubMed
  38. Sattar A, Willman JE, Kolluri R. Possible warfarin resistance due to interaction with ascorbic acid: case report and literature review. Am J Health Syst Pharm. 2013;70(9):782-6. PubMed
  39. Yaich S, Chaabouni Y, Charfeddine K, et al. Secondary oxalosis due to excess vitamin C intake: a cause of graft loss in a renal transplant recipient. Saudi J Kidney Dis Transpl. 2014;25(1):113-6. PubMed
  40. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  41. Rumbold A, Ota E, Nagata C, Shahrook S, Crowther CA. Vitamin C supplementation in pregnancy. Cochrane Database Syst Rev. 2015;(9):CD004072. PubMed
  42. Seo MS, Kim JK, Shim JY. High-dose vitamin C promotes regression of multiple pulmonary metastases originating from hepatocellular carcinoma. Yonsei Med J. 2015;56(5):1449-52. PubMed
  43. Skelin M, Lucijanic T, Amidzic Klaric D, et al. Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review. Clin Ther. 2017 Feb;39(2):378-403. PubMed
  44. Jiang K, Tang K, Liu H, Xu H, Ye Z, Chen Z. Ascorbic acid supplements and kidney stones incidence among men and women: a systematic review and meta-analysis. Urol J. 2019;16(2):115-120.
  45. Thomas S, Patel D, Bittel B, et al. Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical Trial. JAMA Netw Open. 2 PubMed
  46. Giffen MA, McLemore JL. Hyperoxalosis Secondary to Intravenous Vitamin C Administration as a Non-Allopathic Treatment for Cancer. Acad Forensic Pathol 2019;9(1-2):118-126. PubMed
  47. Maike A, Sturgill D, Gallan A. Oxalate Nephropathy in a Renal Transplant Recipient After Receiving High Dose Ascorbic Acid. Am J Med Sci 2021. PubMed
  48. Shen ZY, Chen YR, Wang MC, Chang SS. High-dose vitamin C-induced acute oxalate nephropathy in a renal transplant recipient: a case report and literature review. Asian J Surg 2022. PubMed
  49. Yanase F, Spano S, Maeda A, et al. Mega-dose sodium ascorbate: a pilot, single-dose, physiological effect, double-blind, randomized, controlled trial. Crit Care 2023;27(1):371. PubMed
  50. Sharma Y, Sumanadasa S, Shahi R, et al. Efficacy and safety of vitamin C supplementation in the treatment of community-acquired pneumonia: a systematic review and meta-analysis with trial sequential analysis. Sci Rep 2024;14(1):11846. PubMed
  51. Pejcic AV, Petrovic NZ, Djordjic MD, Milosavljevic MN. Vitamin C Levels in Pregnant Women and the Efficacy of Vitamin C Supplements in Preventing Premature Rupture of Membranes: A Systematic Review and Meta-Analysis. Balkan Med J 2024;41(4):248-260. PubMed

See these in context on the Vitamin C monograph →

Zinc 88 references
  1. Barceloux DG. Zinc. J Toxicol Clin Toxicol 1999;37:279-92.
  2. Eby GA, Davis DR, Halcomb WW. Reduction in duration of common colds by zinc gluconate lozenges in a double-blind study. Antimicrob Agents Chemother 1984;25:20-4. DOI
  3. Smith DS, Helzner EC, Nuttall CE Jr, et al. Failure of zinc gluconate in treatment of acute upper respiratory tract infections. Antimicrob Agents Chemother 1989;33:646-8. PubMed
  4. Blondeau JM. Expanded activity and utility of the new fluoroquinolones: a review. Clin Ther 1999;21:3-40. PubMed
  5. Reyes AJ, Olhaberry JV, Leary WP, et al. Urinary zinc excretion, diuretics, zinc deficiency and some side-effects of diuretics. S Afr Med J 1983;64:936-41.
  6. Kugelmas M. Preliminary observation: oral zinc sulfate replacement is effective in treating muscle cramps in cirrhotic patients. J Am Coll Nutr 2000;19:13-5. PubMed
  7. Hebel SK, ed. Drug Facts and Comparisons. 52nd ed. St. Louis: Facts and Comparisons, 1998.
  8. Chan S, Gerson B, Subramaniam S. The role of copper, molybdenum, selenium, and zinc in nutrition and health. Clin Lab Med 1998;18:673-85. DOI
  9. Brewer GJ, Yuzbasiyan-Gurkan V, Johnson V, et al. Treatment of Wilson's disease with zinc: XI. Interaction with other anticopper agents. J Am Coll Nutr 1993;12:26-30. PubMed
  10. Fosmire GJ. Zinc toxicity. Am J Clin Nutr 1990;51:225-7.
  11. Lomaestro BM, Bailie GR. Absorption interactions with fluoroquinolones. 1995 update. Drug Saf 1995;12:314-33. PubMed
  12. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  13. Seelig MS. Auto-immune complications of D-penicillamine - A possible result of zinc and magnesium depletion and of pyridoxine inactivation. J Am Coll Nutr 1982;1:207-14. PubMed
  14. Neuvonen PJ. Interactions with the absorption of tetracyclines. Drugs 1976;11:45-54.. PubMed
  15. Hirt M, Nobel S, Barron E. Zinc nasal gel for the treatment of common cold symptoms: A double-blind, placebo-controlled trial. Ear Nose Throat J 2000;79:778-82.. DOI
  16. Simkin PA. Oral zinc sulphate in rheumatoid arthritis. Lancet 1976;2:539-42. PubMed
  17. Wray D. A double-blind trial of systemic zinc sulfate in recurrent aphthous stomatitis. Oral Surg Oral Med Oral Pathol 1982;53:469-72. PubMed
  18. Douglas RM, Miles HB, Moore BW, et al. Failure of effervescent zinc acetate lozenges to alter the course of upper respiratory tract infections in Australian adults. Antimicrob Agents Chemother 1987;31:1263-5. PubMed
  19. Lagiou P, Wuu J, Trichopoulou A, et al. Diet and benign prostatic hyperplasia: a study in Greece. Urology 1999;54:284-90. PubMed
  20. Ewing CI, Gibbs AC, Ashcroft C, David TJ. Failure of oral zinc supplementation in atopic eczema. Eur J Clin Nutr 1991;45:507-10.
  21. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  22. Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss. AREDS report no. 8. Arch Oph
  23. Greenberg JE, Lynn M, Kirsner RS, et al. Mucocutaneous pigmented macule as a result of zinc deposition. J Cutan Pathol 2002;29:613-5. PubMed
  24. Godfrey HR, Godfrey NJ, Godfrey JC, Riley D. A randomized clinical trial on the treatment of oral herpes with topical zinc oxide/glycine. Altern Ther Health Med 2001;7:49-56.
  25. Turner RB. Ineffectiveness of intranasal zinc gluconate for prevention of experimental rhinovirus colds. Clin Infect Dis 2001;33:1865-70. PubMed
  26. Belongia EA, Berg R, Liu K. A randomized trial of zinc nasal spray for the treatment of upper respiratory illness in adults. Am J Med 2001;111:103-8. PubMed
  27. Mossad SB. Effect of zincum gluconicum nasal gel on the duration and symptom severity of the common cold in otherwise healthy adults. QJM 2003;96:35-43. DOI
  28. Leitzmann MF, Stampfer MJ, Wu K, et al. Zinc supplement use and risk of prostate cancer. J Natl Cancer Inst 2003;95:1004-7.. PubMed
  29. Jafek BW, Linschoten M, Murrow BW. Zicam Induced Anosmia. American Rhinologic Society 49th Annual Fall Scientific Meeting abstract. Orlando, Florida. September 20, 2003. http://app.american-rhinologic.org/programs/2003ARSFallProgram071503.pdf (Accessed 24
  30. Uebayashi H, Hatanaka T, Kanemura F, Tonosaki K. Acute anosmia in the mouse: behavioral discrimination among the four basic taste substances. Physiol Behav 2001;72:291-6.. PubMed
  31. Barrett S. Zicam Marketers Sued. United States District Court Western District of Michigan Southern Division, Filed October 14, 2003, Case No. 4:03CV0146.
  32. Bilici M, Yildirim F, Kandil S, et al. Double-blind, placebo-controlled study of zinc sulfate in the treatment of attention deficit hyperactivity disorder. Prog Neuropsychopharmacol Biol Psychiatry 2004;28:181-90.. PubMed
  33. Polk RE, Healy DP, Sahai J, et al. Effect of ferrous sulfate and multivitamins with zinc on absorption of ciprofloxacin in normal volunteers. Antimicrob Agents Chemother 1989;33:1841-4. PubMed
  34. Mery C, Delrieu F, Ghozlan R, et al. Controlled trial of D-penicillamine in rheumatoid arthritis. Dose effect and the role of zinc. Scand J Rheumatol 1976;5:241-7. PubMed
  35. Penttila O, Hurme H, Neuvonen PJ. Effect of zinc sulfate on the absorption of tetracycline and doxycycline in man. Eur J Clin Pharmacol 1975;9:131-4.
  36. Kondo Y, Yamagata K, Satoh M, et al. Optimal administration schedule of cisplatin for bladder tumor with minimal induction of metallothionein. J Urol 2003;170:2467-70. PubMed
  37. Doz F, Berens ME, Deschepper CF, et al. Experimental basis for increasing the therapeutic index of cis-diamminedicarboxylatocyclobutaneplatinum(II) in brain tumor therapy by a high-zinc diet. Cancer Chemother Pharmacol 1992;29:219-26.
  38. Wester PO. Urinary zinc excretion during treatment with different diuretics. Acta Med Scand 1980;208:209-12. PubMed
  39. Golik A, Modai D, Weissgarten J, et al. Hydrochlorothiazide-amiloride causes excessive urinary zinc excretion. Clin Pharmacol Ther 1987;42:42-4. PubMed
  40. Leary WP, Reyes AJ, Van der Byl K. Urinary magnesium and zinc excretion after two different single doses of amiloride in healthy adults. Curr Ther Res 1983;34:205-16.
  41. McBride K, Slotnick B, Margolis FL. Does intranasal application of zinc sulfate produce anosmia in the mouse? An olfactometric and anatomical study. Chem Senses 2003;28:659-70. PubMed
  42. Burd GD. Morphological study of the effects of intranasal zinc sulfate irrigation on the mouse olfactory epithelium and olfactory bulb. Microsc Res Tech 1993;24:195-213. PubMed
  43. Ducray A, Bondier JR, Michel G, et al. Recovery following peripheral destruction of olfactory neurons in young and adult mice. Eur J Neurosci 2002;15:1907-17. PubMed
  44. Mayer AD, Rosenblatt JS. Peripheral olfactory deafferentation of the primary olfactory system in rats using ZnSO4 nasal spray with special reference to maternal behavior. Physiol Behav 1993;53:587-92. PubMed
  45. DeCook CA, Hirsch AR. Anosmia due to inhalational zinc: a case report (abstract). Chem Senses 2000;25:659.
  46. Tisdall FF, Brown A, Defries RD. Persistent anosmia following zinc sulfate nasal spraying. JPed 1938;18:60-2. DOI
  47. Lawson KA, Wright ME, Subar A, et al. Multivitamin use and risk of prostate cancer in the National Institutes of Health-AARP Diet and Health Study. J Natl Cancer Inst 2007;99:754-64. PubMed
  48. Public Health Advisory. Loss of sense of smell with intranasal cold remedies containing zinc. U.S. Food and Drug Administration, June 16, 2009. Available at: http://www.fda.gov/Drugs/DrugSafety/PublicHealthAdvisories/ucm166059.htm (Accessed 16 June 2009)
  49. Dooren JC. FDA warns against use of Zicam. The Wall Street Journal, June 16, 2009. Available at: http://online.wsj.com/article/SB124516778692319231.html#mod=djemHL?mg=com-wsj (Accessed 16 June 2009).
  50. Alexander TH, Davidson TM. Intranasal zinc and anosmia: the zinc-induced anosmia syndrome. Laryngoscope 2006;116:217-20.
  51. Health Canada / GlaxoSmithKline Consumer Healthcare. Association of long-term, excessive use of zinc-containing Poli-Grip products with myeloneuropathy and blood dyscrasias. February 18, 2010. Available at: http://hc-sc.gc.ca/dhp-mps/alt_formats/pdf/medef
  52. GlaxoSmithKline Consumer Advisory. GlaxoSmithKline (GSK) warns about a potential health risk associated with long-term, excessive use of GSK's zinc-containing denture adhesives Super Polygrip Original, Ultra Fresh and Extra Care. February 18, 2010. Availa
  53. Science M, Johnstone J, Roth DE, et al. Zinc for the treatment of the common cold: a systematic review and meta-analysis of randomized controlled trials. CMAJ 2012;184:E551-61. PubMed
  54. Castilla-Higuero, L., Romero-Gomez, M., Suarez, E., and Castro, M. Acute hepatitis after starting zinc therapy in a patient with presymptomatic Wilson's disease. Hepatology 2000;32(4 Pt 1):877. PubMed
  55. Sharquie, K. E., Najim, R. A., Farjou, I. B., and Al Timimi, D. J. Oral zinc sulphate in the treatment of acute cutaneous leishmaniasis. Clin.Exp.Dermatol. 2001;26(1):21-26. PubMed
  56. Dreno, B., Moyse, D., Alirezai, M., Amblard, P., Auffret, N., Beylot, C., Bodokh, I., Chivot, M., Daniel, F., Humbert, P., Meynadier, J., and Poli, F. Multicenter randomized comparative double-blind controlled clinical trial of the safety and efficacy of
  57. Moore, R. Bleeding gastric erosion after oral zinc sulphate. Br.Med J 3-25-1978;1(6115):754. PubMed
  58. Jafek, B. W., Linschoten, M. R., and Murrow, B. W. Anosmia after intranasal zinc gluconate use. Am J Rhinol. 2004;18(3):137-141. DOI
  59. Simonart, T. and de, Maertelaer, V. Systemic treatments for cutaneous warts: a systematic review. J Dermatolog.Treat. 2012;23(1):72-77. PubMed
  60. Cochran, R. J., Tucker, S. B., and Flannigan, S. A. Topical zinc therapy for acne vulgaris. Int.J Dermatol. 1985;24(3):188-190. DOI
  61. Morgan, A. A. Bleeding gastric erosion after oral zinc sulphate. Br.Med.J. 5-13-1978;1(6122):1283-1284. PubMed
  62. Murphy, J. V. Intoxication following ingestion of elemental zinc. JAMA 6-22-1970;212(12):2119-2120.
  63. Lang, C. J., Rabas-Kolominsky, P., Engelhardt, A., Kobras, G., and Konig, H. J. Fatal deterioration of Wilson's disease after institution of oral zinc therapy. Arch Neurol. 1993;50(10):1007-1008. PubMed
  64. Fjellner, B. Drug-induced lupus erythematosus aggravated by oral zinc therapy. Acta Derm.Venereol. 1979;59(4):368-370. DOI
  65. Varas Lorenzo, M. J. Zinc acexamate and ranitidine in the short- and mid-term management of gastroduodenal ulcers. Curr Ther Res 21986;39:19-29.
  66. Bosch, F. and Jimenez, E. Post-marketing surveillance of zinc acexamate in peptic ulcer treatment. Clin Trials J 1990;27:301-312.
  67. DeCook, C. A. and Hirsch, A. R. Anosmia due to inhalational zinc: a case report (abstract). Chem Senses 2000;25:659.
  68. Crown LA, May JA. Zinc toxicity: denture adhesives, bone marrow failure and polyneuropathy. Tenn Med. 2012 Feb;105(2):39-40, 42.
  69. Dadamio J, Van Tournout M, Teughels W, Dekeyser C, Coucke W, Quirynen M. Efficacy of different mouthrinse formulations in reducing oral malodour: a randomized clinical trial. J Clin Periodontol. 2013 May;40(5):505-13. PubMed
  70. Moyle G, Else L, Jackson A, Back D, Yapa MH, Seymour N, Ringner-Nackter L, Karolia Z, Gazzard B, Boffito M. Coadministration of atazanavir-ritonavir and zinc sulfate: impact on hyperbilirubinemia and pharmacokinetics. Antimicrob Agents Chemother. 2013 Aug PubMed
  71. Zittel S, Ufer F, Gerloff C, Münchau A, Rosenkranz M. Severe myelopathy after denture cream use--is copper deficiency or excess zinc the cause? Clin Neurol Neurosurg. 2014 Jun;121:17-8. PubMed
  72. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  73. Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents: Drug Interactions between Integrase Inhibitors and Other Drugs. AIDSinfo. July 14, 2016. Available at: https://aidsinfo.nih.gov/guidelines/html/1/adult-and-adolescen
  74. Ding Y, Jia YY, Li F, et al. The effect of staggered administration of zinc sulfate on the pharmacokinetics of oral cephalexin. Br J Clin Pharmacol. 2012 Mar;73(3):422-7. PubMed
  75. Fallah R, Sabbaghzadegan S, Karbasi SA, Binesh F. Efficacy of zinc sulfate supplement on febrile seizure recurrence prevention in children with normal serum zinc level: A randomised clinical trial. Nutrition. 2015;31(11-12):1358-61. PubMed
  76. Lazzerini M, Wanzira H. Oral zinc for treating diarrhoea in children. Cochrane Database Syst Rev. 2016;12:CD005436. PubMed
  77. Mahmoud AM, Al-Alem U, Dabbous F, et al. Zinc intake and risk of prostate cancer: Case-control study and meta-analysis. PLoS One. 2016;11(11):e0165956. PubMed
  78. Nagraj SK, George RP, Shetty N, Levenson D, Ferraiolo DM, Shrestha A. Interventions for managing taste disturbances. Cochrane Database Syst Rev. 2017 Dec 20;12(12):CD010470. PubMed
  79. Yee BE, Richards P, Sui JY, Marsch AF. Serum zinc levels and efficacy of zinc treatment in acne vulgaris: A systematic review and meta-analysis. Dermatol Ther. 2020:e14252. PubMed
  80. Janyajirawong R, Vilaichone RK, Sethasine S. Efficacy of zinc supplement in minimal hepatic encephalopathy: A prospective, randomized controlled study (Zinc-MHE Trial). Asian Pac J Cancer Prev 2021;22(9):2879-2887. PubMed
  81. Nakano M, Nakamura Y, Miyazaki A, Takahashi J. Zinc pharmacotherapy for elderly osteoporotic patients with zinc deficiency in a clinical setting. Nutrients 2021;13(6):1814. PubMed
  82. Tolino E, Skroza N, Mambrin A, et al. An open-label study comparing oral zinc to lymecycline in the treatment of acne vulgaris. J Clin Aesthet Dermatol 2021;14(5):56-58.
  83. Hunter J, Arentz S, Goldenberg J, et al. Zinc for the prevention or treatment of acute viral respiratory tract infections in adults: a rapid systematic review and meta-analysis of randomised controlled trials. BMJ Open. 2021;11(11):e047474. PubMed
  84. Yamazaki K, Kageyama H, Fujiyama T, Ito T, Urano S, Honda T. A case of systemic contact dermatitis due to zinc supplements. Int J Dermatol 2022. PubMed
  85. Magham K, Han J, Eilbert W, Bunney EB. Severe copper deficiency anemia caused by zinc supplement use. Am J Emerg Med 2023;72:222. PubMed
  86. Sivakumar RR, Chinnaiah Govindareddy D, Sahoo J, Bobby Z, Chinnakali P. Effect of daily zinc supplementation for 12 weeks on serum thyroid auto-antibody levels in children and adolescents with autoimmune thyroiditis - a randomized controlled trial. J Pedi PubMed
  87. AlDhasee O, AlMalki H, AlKharashi N, AlJeraisy N, Al Deeb M. Acute zinc sulfate overdose: clinical presentation and management. BMJ Case Rep 2025;18(1):e263899. PubMed
  88. US Food and Drug Administration (FDA). Biktarvy Prescribing Information. October 2024. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/210251Orig1s020lbl.pdf. Accessed July 16, 2025.

See these in context on the Zinc monograph →

Grapefruit 157 references
  1. Penzak SR, Gubbins PO, Gurley BJ, et al. Grapefruit juice decreases the systemic availability of itraconazole capsules in healthy volunteers. Ther Drug Monit 1999;21:304-9. PubMed
  2. Ioannides-Demos LL, Christophidis N, et al. Dosing implications of a clinical interaction between grapefruit juice and cyclosporine and metabolite concentrations in patients with autoimmune diseases. J Rheumatol 1997;24:49-54.
  3. Josefsson M, Zackrisson AL, Ahlner J. Effect of grapefruit juice on the pharmacokinetics of amlodipine in healthy volunteers. Eur J Clin Pharmacol 1996;51:189-93. PubMed
  4. Garg SK, Kumar N, Bhargava VK, Prabhakar SK. Effect of grapefruit juice on carbamazepine bioavailability in patients with epilepsy. Clin Pharmacol Ther 1998;64:286-8. PubMed
  5. Weber A, Jager R, Borner A, et al. Can grapefruit juice influence ethinylestradiol bioavailability? Contraception 1996;53:41-7.
  6. Schubert W, Cullberg G, Edgar B, Hedner T. Inhibition of 17 beta-estradiol metabolism by grapefruit juice in ovariectomized women. Maturitas 1994;20:155-63.
  7. Kantola T, Kivisto KT, Neuvonen PJ, et al. Grapefruit juice greatly increases serum concentrations of lovastatin and lovastatin acid. Clin Pharmacol Ther 1998 63:397-402. PubMed
  8. Bailey DG, Spence JD, Munoz C, Arnold JM. Interaction of citrus juices with felodipine and nifedipine. Lancet 1991;337:268-9. PubMed
  9. Bailey DG, Arnold JM, Strong HA, et al. Effect of grapefruit juice and naringin on nisoldipine pharmacokinetics. Clin Pharmacol Ther 1993;54:589-94. PubMed
  10. Rau SE, Bend JR, Arnold MO, et al. Grapefruit juice-terfenadine single-dose interaction: magnitude, mechanism, and relevance. Clin Pharmacol Ther 1997 61:401-9. PubMed
  11. Offman EM, Freeman DJ, Dresser GK, et al. Cisapride interaction with grapefruit juice and red wine. Clin Pharmacol Ther 2000;67:110 (abstract PI-83).
  12. Bailey DG, Dresser GK, Kreeft JH, et al. Grapefruit juice-felodipine interaction: Effect of segments and an extract from unprocessed fruit. Clin Pharmacol Ther 2000;67:107 (abstract PI-71).
  13. Soldner A, Christians U, Susanto M, et al. Grapefruit juice activates P-glycoprotein-mediated drug transport. Pharm Res 1999;16:478-85. PubMed
  14. Zaidenstein R, Avni B, Dishi V, et al. Effect of grapefruit juice on the pharmacokinetics of losartan in healthy volunteers. Clin Pharmacol Ther 1998;65:(abstract PI-60). DOI
  15. Dresser GK, Bailey DG, Carruthers SG. Grapefruit juice-felodipine interaction in healthy seniors. Clin Pharmacol Ther 1998;65:(abstract PIII-63).
  16. Varis T, Kivisto KT, Neuvonen PJ. Grapefruit juice can increase the plasma concentration of methylprednisolone. Eur J Clin Pharmacol 2000;56:489-93.
  17. Gross AS, Goh YD, Addison RS, et al. Influence of grapefruit juice on cisapride pharmacokinetics. Clin Pharmacol Ther 1999;65:395-401. PubMed
  18. Lilja JJ, Kivisto KT, Neuvonen PJ. Grapefruit juice increases serum concentrations of atorvastatin and has no effect on pravastatin. Clin Pharmacol Ther 1999;66:118-27. DOI
  19. Ozdemir M, Aktan Y, Boydag BS. Interaction between grapefruit juice and diazepam in humans. Eur J Drug Metab Pharmacokinet 1998;23:55-9. PubMed
  20. Zaidenstein R, Dishi V, Gips M, et al. The effect of grapefruit juice on the pharmacokinetics of orally administered verapamil. Eur J Clin Pharmacol 1998;54:337-40. PubMed
  21. Lilja JJ, Kivisto KT, Backman JT, et al. Grapefruit juice substantially increases plasma concentrations of buspirone. Clin Pharmacol Ther 1998;64:655-60. PubMed
  22. Kupferschmidt HH, Fattinger KE, Ha HR, et al. Grapefruit juice enhances the bioavailability of the HIV protease inhibitor saquinavir in man. Br J Clin Pharmacol 1998;45:355-9. DOI
  23. Lilja JJ, Kivisto KT, Neuvonen PJ. Grapefruit juice-simvastatin interaction: effect on serum concentrations of simvastatin, simvastatin acid, and HMG-CoA reductase inhibitors. Clin Pharmacol Ther 1998;64:477-83. PubMed
  24. Curhan GC, Willett WC, Speizer FE, Stamfer MJ. Beverage use and risk of kidney stones in women. Ann Intern Med 1998;128:534-40.
  25. Fuhr U. Drug Interactions with Grapefruit Juice. Drug Saf 1998;18:251-72. DOI
  26. Oesterheld J, Kallepalli BR. Grapefruit juice and clomipramine: shifting metabolitic ratios. J Clin Psychopharmacol 1997;17:62-3. PubMed
  27. van Agtmael MA, Gupta V, van der Wosten TH, et al. Grapefruit juice increases the bioavailability of artemether. Eur J Clin Pharmacol 1999;55:405-10. PubMed
  28. van Agtmael MA, Gupta V, van der Graaf CA, van Boxtel CJ. The effect of grapefruit juice on the time-dependent decline of artemether plasma levels in healthy subjects. Clin Pharmacol Ther 1999;66:408-14.
  29. Damkier P, Hansen LL, Brosen K. Effect of diclofenac, disulfiram, itraconazole, grapefruit juice and erythromycin on the pharmacokinetics of quinidine. Br J Clin Pharmacol 1999;48:829-38. PubMed
  30. Takanaga H, Ohnishi A, Murakami H, et al. Relationship between time after intake of grapefruit juice and the effect on pharmacokinetics and pharmacodynamics of nisoldipine in healthy subjects. Clin Pharmacol Ther 2000:67:201-14. PubMed
  31. Takanaga H, Ohnishi A, Matsuo H, et al. Pharmacokinetic analysis of felodipine-grapefruit juice interaction based on an irreversible enzyme inhibition model. Br J Clin Pharmacol 2000;49:49-58. PubMed
  32. Coreg monograph. In: Gillis MC, Ed. Compendium of Pharmaceuticals and Specialities (CPS). 34th ed. Ottawa, Ontario, CAN:Canadian Pharmacists Assn, 1999:395.
  33. Dresser GK, Bailey DG, Carruthers SG. Grapefruit juice-felodipine interaction in the elderly. Clin Pharmacol Ther 2000;68:28-34. PubMed
  34. Bailey DG, Dresser GK, Munoz C, et al. Reduction of fexofenadine bioavailability by fruit juices. Clin Pharmacol Ther 2001;69:P21.
  35. Lilja JJ, Kivisto KT, Backman JT, Neuvonen PJ. Effect of grapefruit juice dose on grapefruit juice-triazolam interaction: repeated consumption prolongs triazolam half-life. Eur J Clin Pharmacol 2000;56:411-5. PubMed
  36. Erlund I, Meririnne E, Alfthan G, Aro A. Plasma kinetics and urinary excretion of the flavanones naringenin and hesperetin in humans after ingestion of orange juice and grapefruit juice. J Nutr 2001;131:235-41. PubMed
  37. Ho PC, Ghose K, Saville D, Wanwimolruk S. Effect of grapefruit juice on pharmacokinetics and pharmacodynamics of verapamil enantiomers in healthy volunteers. Eur J Clin Pharmacol 2000;56:693-8. PubMed
  38. Uno T, Ohkubo T, Sugawara K, et al. Effects of grapefruit juice on the stereoselective disposition of nicardipine in humans: evidence for dominant presystemic elimination at the gut site. Eur J Clin Pharmacol 2000;56:643-9. PubMed
  39. Bailey DG, Dresser GK. Grapefruit juice-lovastatin interaction. Clin Pharmacol Ther 2000;67:690.
  40. Lilja JJ, Kivisto KT, Neuvonen PJ. Duration of effect of grapefruit juice on the pharmacokinetics of the CYP3A4 substrate simvastatin. Clin Pharmacol Ther 2000;68:384-90. PubMed
  41. Castro N, Jung H, Medina R, et al. Interaction between grapefruit juice and praziquantel in humans. Antimicrob Agents Chemother 2002;46:1614-6. PubMed
  42. Jetter A, Kinzig-Schippers M, Walchner-Bonjean M, et al. Effects of grapefruit juice on the pharmacokinetics of sildenafil. Clin Pharmacol Ther 2002;71:21-9. PubMed
  43. Ebert U, Oertel R, Kirch W. Influence of grapefruit juice on scopolamine pharmacokinetics and pharmacodynamics in healthy male and female subjects. Int J Clin Pharmacol Ther 2000;38:523-31. PubMed
  44. Fuhr U, Muller-Peltzer H, Kern R, et al. Effects of grapefruit juice and smoking on verapamil concentrations in steady state. Eur J Clin Pharmacol 2002;58:45-53. PubMed
  45. Kanazawa S, Ohkubo T, Sugawara K. The effects of grapefruit juice on the pharmacokinetics of erythromycin. Eur J Clin Pharmacol 2001;56:799-803. PubMed
  46. Reif S, Nicolson M, Bisset D, et al. Effect of grapefruit juice intake on etoposide bioavailability. Eur J Clin Pharmacol 2002;58:491-4.. PubMed
  47. Greenblatt DJ, von Moltke LL, Harmatz JS. Time course of recovery of cytochrome P450 3A function after single doses of grapefruit juice. Clin Pharmacol Ther 2003;74:121-29 . PubMed
  48. Gupta MC, Garg SK, Badyal D, et al. Effect of grapefruit juice on the pharmacokinetics of theophylline in healthy male volunteers. Methods Find Exp Clin Pharmacol 1999;21:679-82. PubMed
  49. Edwards DJ, Fitzsimmons ME, Schuetz EG, et al. 6',7'-Dihydroxybergamottin in grapefruit juice and Seville orange juice: effects on cyclosporine disposition, enterocyte CYP3A4, and P-glycoprotein. Clin Pharmacol Ther 1999;65:237-44. PubMed
  50. Rogers JD, Zhao J, Liu L, et al. Grapefruit juice has minimal effects on plasma concentrations of lovastatin-derived 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors. Clin Pharmacol Ther 1999;66:358-66. PubMed
  51. Veronese ML, Gillen LP, Burke JP, et al. Exposure-dependent inhibition of intestinal and hepatic CYP3A4 in vivo by grapefruit juice. J Clin Pharmacol 2003;43:831-9. . PubMed
  52. Bailey DG, Dresser GK, Bend JR. Bergamottin, lime juice, and red wine as inhibitors of cytochrome P450 3A4 activity: comparison with grapefruit juice. Clin Pharmacol Ther 2003;73:529-37 . PubMed
  53. Becquemont L, Verstuyft C, Kerb R, et al. Effect of grapefruit juice on digoxin pharmacokinetics in humans. Clin Pharmacol Ther 2001;70:311-6. DOI
  54. Dresser GK, Bailey DG, Leake BF, et al. Fruit juices inhibit organic anion transporting polypeptide-mediated drug uptake to decrease the oral availability of fexofenadine. Clin Pharmacol Ther 2002;71:11-20. PubMed
  55. Parker RB, Yates CR, Soberman JE, Laizure SC. Effects of grapefruit juice on intestinal P-glycoprotein: evaluation using digoxin in humans. Pharmacotherapy 2003;23:979-87. PubMed
  56. Di Marco MP, Edwards DJ, Wainer IW, Ducharme MP. The effect of grapefruit juice and seville orange juice on the pharmacokinetics of dextromethorphan: the role of gut CYP3A and P-glycoprotein. Life Sci 2002;71:1149-60. PubMed
  57. Gaudineau C, Beckerman R, Welbourn S, Auclair K. Inhibition of human P450 enzymes by multiple constituents of the Ginkgo biloba extract. Biochem Biophys Res Comm 2004;318:1072–8. PubMed
  58. Sullivan DM, Ford MA, Boyden TW. Grapefruit juice and the response to warfarin. Am J Health-Syst Pharm 1998;55:1581-3. PubMed
  59. Fukazawa I, Uchida N, Uchida E, Yasuhara H. Effects of grapefruit juice on the pharmacokinetics of atorvastatin and pravastatin in Japanese. Br J Clin Pharmacol 2003;57:448-55.
  60. Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1 PubMed
  61. Zitron E, Scholz E, Owen RW, et al. QTc prolongation by grapefruit juice and its potential pharmacological basis: HERG channel blockade by flavonoids. Circulation 2005;835:835-8. PubMed
  62. Monroe KR, Murphy SP, Kolonel LN, Pike MC. Prospective study of grapefruit intake and risk of breast cancer in postmenopausal women: the Mutliethnic Cohort Study. Br J Cancer 2007;97:440-5.
  63. Farkas D, Oleson LE, Zhao Y, et al. Pomegranate juice does not impair clearance of oral or intravenous midazolam, a probe for cytochrome P450-3A activity: comparison with grapefruit juice. J Clin Pharmacol 2007;47:286-94. PubMed
  64. Potential drug interactions with grapefruit. Pharmacist's Letter / Prescriber's Letter 2007;23(2):230204.
  65. Dresser GK, Kim RB, Bailey DG. Effect of grapefruit juice volume on the reduction of fexofenadine bioavailability: possible role of organic anion transporting polypeptides. Clin Pharmacol Ther 2005;77:170-7. PubMed
  66. Greenblatt DJ. Analysis of drug interactions involving fruit beverages and organic anion-transporting polypeptides. J Clin Pharmacol 2009;49:1403-7. PubMed
  67. Bailey DG. Fruit juice inhibition of uptake transport: a new type of food-drug interaction. Br J Clin Pharmacol 2010;70:645-55. PubMed
  68. Product information for Cordarone. Wyeth Pharmaceuticals, Inc. Philadelphia, PA 19101. September 2006.
  69. Demarles D, Gillotin C, Bonaventure-Paci S, et al. Single-dose pharmacokinetics of amprenavir coadministered with grapefruit juice. Antimicrob Agents Chemother 2002;46:1589-90. PubMed
  70. Yasui N, Kondo T, Furukori H, et al. Effects of repeated ingestion of grapefruit juice on the single and multiple oral-dose pharmacokinetics and pharmacodynamics of alprazolam. Psychopharmacology (Berl) 2000;150:185-90. PubMed
  71. Hori H, Yoshimura R, Ueda N, et al. Grapefruit juice-fluvoxamine interaction -- is it risky or not? J Clin Psychopharmacol 2003;23:422-4. PubMed
  72. Benmebarek M, Devaud C, Gex-Fabry M, et al. Effects of grapefruit juice on the pharmacokinetics of the enantiomers of methadone. Clin Pharmacol Ther 2004;76:55-63.
  73. Yin OQ, Gallagher N, Li A, et al. Effect of grapefruit juice on the pharmacokinetics of nilotinib in healthy participants. J Clin Pharmacol 2010;50:188-94. PubMed
  74. Lilja JJ, Raaska K, Neuvonen PJ. Effects of grapefruit juice on the pharmacokinetics of acebutolol. Br J Clin Pharmacol 2005;60:659-63. PubMed
  75. Hollander, A. A., van Rooij, J., Lentjes, G. W., Arbouw, F., van Bree, J. B., Schoemaker, R. C., van Es, L. A., van der Woude, F. J., and Cohen, A. F. The effect of grapefruit juice on cyclosporine and prednisone metabolism in transplant patients. Clin Ph PubMed
  76. Sigusch, H., Hippius, M., Henschel, L., Kaufmann, K., and Hoffmann, A. Influence of grapefruit juice on the pharmacokinetics of a slow release nifedipine formulation. Pharmazie 1994;49(7):522-524.
  77. Andersen, V., Pedersen, N., Larsen, N. E., Sonne, J., and Larsen, S. Intestinal first pass metabolism of midazolam in liver cirrhosis --effect of grapefruit juice. Br J Clin Pharmacol 2002;54(2):120-124. PubMed
  78. Hukkinen, S. K., Varhe, A., Olkkola, K. T., and Neuvonen, P. J. Plasma concentrations of triazolam are increased by concomitant ingestion of grapefruit juice. Clin Pharmacol Ther 1995;58(2):127-131. PubMed
  79. Kupferschmidt, H. H., Ha, H. R., Ziegler, W. H., Meier, P. J., and Krahenbuhl, S. Interaction between grapefruit juice and midazolam in humans. Clin Pharmacol Ther 1995;58(1):20-28. PubMed
  80. Libersa, C. C., Brique, S. A., Motte, K. B., Caron, J. F., Guedon-Moreau, L. M., Humbert, L., Vincent, A., Devos, P., and Lhermitte, M. A. Dramatic inhibition of amiodarone metabolism induced by grapefruit juice. Br J Clin Pharmacol 2000;49(4):373-378. PubMed
  81. Min, D. I., Ku, Y. M., Geraets, D. R., and Lee, H. Effect of grapefruit juice on the pharmacokinetics and pharmacodynamics of quinidine in healthy volunteers. J Clin Pharmacol 1996;36(5):469-476. PubMed
  82. Lee, A. J., Chan, W. K., Harralson, A. F., Buffum, J., and Bui, B. C. The effects of grapefruit juice on sertraline metabolism: an in vitro and in vivo study. Clin Ther 1999;21(11):1890-1899. PubMed
  83. Kawakami, M., Suzuki, K., Ishizuka, T., Hidaka, T., Matsuki, Y., and Nakamura, H. Effect of grapefruit juice on pharmacokinetics of itraconazole in healthy subjects. Int J Clin Pharmacol Ther 1998;36(6):306-308.
  84. Benton, R. E., Honig, P. K., Zamani, K., Cantilena, L. R., and Woosley, R. L. Grapefruit juice alters terfenadine pharmacokinetics, resulting in prolongation of repolarization on the electrocardiogram. Clin Pharmacol Ther 1996;59(4):383-388. PubMed
  85. Clifford, C. P., Adams, D. A., Murray, S., Taylor, G. W., Wilkins, M. R., Boobis, A. R., and Davies, D. S. The cardiac effects of terfenadine after inhibition of its metabolism by grapefruit juice. Eur J Clin Pharmacol 1997;52(4):311-315. PubMed
  86. Ando, H., Tsuruoka, S., Yanagihara, H., Sugimoto, K., Miyata, M., Yamazoe, Y., Takamura, T., Kaneko, S., and Fujimura, A. Effects of grapefruit juice on the pharmacokinetics of pitavastatin and atorvastatin. Br J Clin Pharmacol 2005;60(5):494-497. DOI
  87. Lilja, J. J., Neuvonen, M., and Neuvonen, P. J. Effects of regular consumption of grapefruit juice on the pharmacokinetics of simvastatin. Br J Clin Pharmacol 2004;58(1):56-60. PubMed
  88. Charbit, B., Becquemont, L., Lepere, B., Peytavin, G., and Funck-Brentano, C. Pharmacokinetic and pharmacodynamic interaction between grapefruit juice and halofantrine. Clin Pharmacol Ther 2002;72(5):514-523. PubMed
  89. Cuong, B. T., Binh, V. Q., Dai, B., Duy, D. N., Lovell, C. M., Rieckmann, K. H., and Edstein, M. D. Does gender, food or grapefruit juice alter the pharmacokinetics of primaquine in healthy subjects? Br J Clin Pharmacol 2006;61(6):682-689. PubMed
  90. Culm-Merdek, K. E., von Moltke, L. L., Gan, L., Horan, K. A., Reynolds, R., Harmatz, J. S., Court MH, and Greenblatt, D. J. Effect of extended exposure to grapefruit juice on cytochrome P450 3A activity in humans: comparison with ritonavir. Clin Pharmacol
  91. Hugen, P. W., Burger, D. M., Koopmans, P. P., Stuart, J. W., Kroon, F. P., van Leusen, R., and Hekster, Y. A. Saquinavir soft-gel capsules (Fortovase) give lower exposure than expected, even after a high-fat breakfast. Pharm World Sci 2002;24(3):83-86.
  92. Sugimoto, K., Araki, N., Ohmori, M., Harada, K., Cui, Y., Tsuruoka, S., Kawaguchi, A., and Fujimura, A. Interaction between grapefruit juice and hypnotic drugs: comparison of triazolam and quazepam. Eur J Clin Pharmacol 2006;62(3):209-215. PubMed
  93. Lilja, J. J., Backman, J. T., Laitila, J., Luurila, H., and Neuvonen, P. J. Itraconazole increases but grapefruit juice greatly decreases plasma concentrations of celiprolol. Clin Pharmacol Ther 2003;73(3):192-198. PubMed
  94. Schwarz, U. I., Seemann, D., Oertel, R., Miehlke, S., Kuhlisch, E., Fromm, M. F., Kim, R. B., Bailey, D. G., and Kirch, W. Grapefruit juice ingestion significantly reduces talinolol bioavailability. Clin Pharmacol Ther 2005;77(4):291-301. PubMed
  95. Bailey, D. G., Arnold, J. M., Munoz, C., and Spence, J. D. Grapefruit juice--felodipine interaction: mechanism, predictability, and effect of naringin. Clin Pharmacol Ther 1993;53(6):637-642. PubMed
  96. Bailey, D. G., Arnold, J. M., Bend, J. R., Tran, L. T., and Spence, J. D. Grapefruit juice-felodipine interaction: reproducibility and characterization with the extended release drug formulation. Br J Clin Pharmacol 1995;40(2):135-140.
  97. Christensen, H., Asberg, A., Holmboe, A. B., and Berg, K. J. Coadministration of grapefruit juice increases systemic exposure of diltiazem in healthy volunteers. Eur J Clin Pharmacol 2002;58(8):515-520. PubMed
  98. Edgar, B., Bailey, D., Bergstrand, R., Johnsson, G., and Regardh, C. G. Acute effects of drinking grapefruit juice on the pharmacokinetics and dynamics of felodipine--and its potential clinical relevance. Eur J Clin Pharmacol 1992;42(3):313-317.
  99. Goosen, T. C., Cillie, D., Bailey, D. G., Yu, C., He, K., Hollenberg, P. F., Woster, P. M., Cohen, L., Williams, J. A., Rheeders, M., and Dijkstra, H. P. Bergamottin contribution to the grapefruit juice-felodipine interaction and disposition in humans. Cl PubMed
  100. Fuhr, U., Maier-Bruggemann, A., Blume, H., Muck, W., Unger, S., Kuhlmann, J., Huschka, C., Zaigler, M., Rietbrock, S., and Staib, A. H. Grapefruit juice increases oral nimodipine bioavailability. Int J Clin Pharmacol Ther 1998;36(3):126-132.
  101. Hashimoto, K., Shirafuji, T., Sekino, H., Matsuoka, O., Sekino, H., Onnagawa, O., Okamoto, T., Kudo, S., and Azuma, J. Interaction of citrus juices with pranidipine, a new 1,4-dihydropyridine calcium antagonist, in healthy subjects. Eur J Clin Pharmacol 1 PubMed
  102. Lundahl, J., Regardh, C. G., Edgar, B., and Johnsson, G. Effects of grapefruit juice ingestion--pharmacokinetics and haemodynamics of intravenously and orally administered felodipine in healthy men. Eur J Clin Pharmacol 1997;52(2):139-145. PubMed
  103. Lundahl, J., Regardh, C. G., Edgar, B., and Johnsson, G. Relationship between time of intake of grapefruit juice and its effect on pharmacokinetics and pharmacodynamics of felodipine in healthy subjects. Eur J Clin Pharmacol 1995;49(1-2):61-67. PubMed
  104. Rashid, T. J., Martin, U., Clarke, H., Waller, D. G., Renwick, A. G., and George, C. F. Factors affecting the absolute bioavailability of nifedipine. Br J Clin Pharmacol 1995;40(1):51-58. PubMed
  105. Soons, P. A., Vogels, B. A., Roosemalen, M. C., Schoemaker, H. C., Uchida, E., Edgar, B., Lundahl, J., Cohen, A. F., and Breimer, D. D. Grapefruit juice and cimetidine inhibit stereoselective metabolism of nitrendipine in humans. Clin Pharmacol Ther 1991; PubMed
  106. Rashid, J., McKinstry, C., Renwick, A. G., Dirnhuber, M., Waller, D. G., and George, C. F. Quercetin, an in vitro inhibitor of CYP3A, does not contribute to the interaction between nifedipine and grapefruit juice. Br J Clin Pharmacol 1993;36(5):460-463.
  107. Uno, T., Ohkubo, T., Motomura, S., and Sugawara, K. Effect of grapefruit juice on the disposition of manidipine enantiomers in healthy subjects. Br J Clin Pharmacol 2006;61(5):533-537. DOI
  108. Bistrup, C., Nielsen, F. T., Jeppesen, U. E., and Dieperink, H. Effect of grapefruit juice on Sandimmun Neoral absorption among stable renal allograft recipients. Nephrol Dial.Transplant. 2001;16(2):373-377. PubMed
  109. Ducharme, M. P., Warbasse, L. H., and Edwards, D. J. Disposition of intravenous and oral cyclosporine after administration with grapefruit juice. Clin Pharmacol Ther 1995;57(5):485-491. PubMed
  110. Ku, Y. M., Min, D. I., and Flanigan, M. Effect of grapefruit juice on the pharmacokinetics of microemulsion cyclosporine and its metabolite in healthy volunteers: does the formulation difference matter? J Clin Pharmacol 1998;38(10):959-965. PubMed
  111. Lee, M., Min, D. I., Ku, Y. M., and Flanigan, M. Effect of grapefruit juice on pharmacokinetics of microemulsion cyclosporine in African American subjects compared with Caucasian subjects: does ethnic difference matter? J Clin Pharmacol 2001;41(3):317-323 PubMed
  112. Schwarz, U. I., Johnston, P. E., Bailey, D. G., Kim, R. B., Mayo, G., and Milstone, A. Impact of citrus soft drinks relative to grapefruit juice on ciclosporin disposition. Br J Clin Pharmacol 2006;62(4):485-491. PubMed
  113. Yee, G. C., Stanley, D. L., Pessa, L. J., Dalla, Costa T., Beltz, S. E., Ruiz, J., and Lowenthal, D. T. Effect of grapefruit juice on blood cyclosporin concentration. Lancet 4-15-1995;345(8955):955-956. PubMed
  114. Paine, M. F., Widmer, W. W., Hart, H. L., Pusek, S. N., Beavers, K. L., Criss, A. B., Brown, S. S., Thomas, B. F., and Watkins, P. B. A furanocoumarin-free grapefruit juice establishes furanocoumarins as the mediators of the grapefruit juice-felodipine in
  115. Sigusch, H., Henschel, L., Kraul, H., Merkel, U., and Hoffmann, A. Lack of effect of grapefruit juice on diltiazem bioavailability in normal subjects. Pharmazie 1994;49(9):675-679.
  116. Fingerova, H., Oborna, I., Petrova, P., Budikova, M., and Jezdinsky, J. [Does grapefruit juice increase the bioavailability of orally administered sex steroids?]. Ceska.Gynekol. 2003;68(2):117-121.
  117. Glaeser, H., Bailey, D. G., Dresser, G. K., Gregor, J. C., Schwarz, U. I., McGrath, J. S., Jolicoeur, E., Lee, W., Leake, B. F., Tirona, R. G., and Kim, R. B. Intestinal drug transporter expression and the impact of grapefruit juice in humans. Clin Pharma PubMed
  118. Lilja, J. J., Laitinen, K., and Neuvonen, P. J. Effects of grapefruit juice on the absorption of levothyroxine. Br J Clin Pharmacol 2005;60(3):337-341. PubMed
  119. Kivisto, K. T., Lilja, J. J., Backman, J. T., and Neuvonen, P. J. Repeated consumption of grapefruit juice considerably increases plasma concentrations of cisapride. Clin Pharmacol Ther 1999;66(5):448-453. PubMed
  120. Desta, Z., Kivisto, K. T., Lilja, J. J., Backman, J. T., Soukhova, N., Neuvonen, P. J., and Flockhart, D. A. Stereoselective pharmacokinetics of cisapride in healthy volunteers and the effect of repeated administration of grapefruit juice. Br J Clin Pharm PubMed
  121. Odou, P., Ferrari, N., Barthelemy, C., Brique, S., Lhermitte, M., Vincent, A., Libersa, C., and Robert, H. Grapefruit juice-nifedipine interaction: possible involvement of several mechanisms. J Clin Pharm Ther 2005;30(2):153-158. PubMed
  122. Wason, S., DiGiacinto, J. L., and Davis, M. W. Effects of grapefruit and Seville orange juices on the pharmacokinetic properties of colchicine in healthy subjects. Clin Ther 2012;34(10):2161-2173. PubMed
  123. Bailey, D. G., Dresser, G. K., Kreeft, J. H., Munoz, C., Freeman, D. J., and Bend, J. R. Grapefruit-felodipine interaction: effect of unprocessed fruit and probable active ingredients. Clin Pharmacol Ther 2000;68(5):468-477. PubMed
  124. Kumar, A., Teuber, S. S., Naguwa, S., Prindiville, T., and Gershwin, M. E. Eosinophilic gastroenteritis and citrus-induced urticaria. Clin Rev Allergy Immunol 2006;30(1):61-70. PubMed
  125. Ferdman, R. M., Ong, P. Y., and Church, J. A. Pectin anaphylaxis and possible association with cashew allergy. Ann.Allergy Asthma Immunol. 2006;97(6):759-760. PubMed
  126. Guo, L. Q., Chen, Q. Y., Wang, X., Liu, Y. X., Chu, X. M., Cao, X. M., Li, J. H., and Yamazoe, Y. Different roles of pummelo furanocoumarin and cytochrome P450 3A5*3 polymorphism in the fate and action of felodipine. Curr Drug Metab 2007;8(6):623-630. PubMed
  127. Curhan, G. C., Willett, W. C., Rimm, E. B., Spiegelman, D., and Stampfer, M. J. Prospective study of beverage use and the risk of kidney stones. Am J Epidemiol. 2-1-1996;143(3):240-247. PubMed
  128. Holmberg MT, Tornio A, Joutsi-Korhonen L, Neuvonen M, Neuvonen PJ, Lassila R, Niemi M, Backman JT. Grapefruit juice markedly increases the plasma concentrations and antiplatelet effects of ticagrelor in healthy subjects. Br J Clin Pharmacol. 2013 Jun;75(6 PubMed
  129. Holmberg MT, Tornio A, Neuvonen M, Neuvonen PJ, Backman JT, Niemi M. Grapefruit juice inhibits the metabolic activation of clopidogrel. Clin Pharmacol Ther. 2014 Mar;95(3):307-13. PubMed
  130. Hu M, Mak VW, Yin OQ, Chu TT, Tomlinson B. Effects of grapefruit juice and SLCO1B1 388A>G polymorphism on the pharmacokinetics of pitavastatin. Drug Metab Pharmacokinet. 2013;28(2):104-8.
  131. Ieiri I, Doi Y, Maeda K, Sasaki T, Kimura M, Hirota T, Chiyoda T, Miyagawa M, Irie S, Iwasaki K, Sugiyama Y. Microdosing clinical study: pharmacokinetic, pharmacogenomic (SLCO2B1), and interaction (grapefruit juice) profiles of celiprolol following the or
  132. Misaka S, Miyazaki N, Yatabe MS, Ono T, Shikama Y, Fukushima T, Kimura J. Pharmacokinetic and pharmacodynamic interaction of nadolol with itraconazole, rifampicin and grapefruit juice in healthy volunteers. J Clin Pharmacol. 2013 Jul;53(7):738-45. PubMed
  133. Nieminen TH, Hagelberg NM, Saari TI, Neuvonen M, Neuvonen PJ, Laine K, Olkkola KT. Grapefruit juice enhances the exposure to oral oxycodone. Basic Clin Pharmacol Toxicol. 2010 Oct;107(4):782-8. PubMed
  134. Piccirillo G, Magrì D, Matera S, Magnanti M, Pasquazzi E, Schifano E, Velitti S, Mitra M, Marigliano V, Paroli M, Ghiselli A. Effects of pink grapefruit juice on QT variability in patients with dilated or hypertensive cardiomyopathy and in healthy subject
  135. Seidegård J, Randvall G, Nyberg L, Borgå O. Grapefruit juice interaction with oral budesonide: equal effect on immediate-release and delayed-release formulations. Pharmazie. 2009 Jul;64(7):461-5. DOI
  136. Shoaf SE, Mallikaarjun S, Bricmont P. Effect of grapefruit juice on the pharmacokinetics of tolvaptan, a non-peptide arginine vasopressin antagonist, in healthy subjects. Eur J Clin Pharmacol. 2012 Feb;68(2):207-11. PubMed
  137. Tanaka S, Uchida S, Miyakawa S, Inui N, Takeuchi K, Watanabe H, Namiki N. Comparison of inhibitory duration of grapefruit juice on organic anion-transporting polypeptide and cytochrome P450 3A4. Biol Pharm Bull. 2013;36(12):1936-41. PubMed
  138. Tapaninen T, Neuvonen PJ, Niemi M. Grapefruit juice greatly reduces the plasma concentrations of the OATP2B1 and CYP3A4 substrate aliskiren. Clin Pharmacol Ther. 2010 Sep;88(3):339-42. PubMed
  139. van Erp NP, Baker SD, Zandvliet AS, Ploeger BA, den Hollander M, Chen Z, den Hartigh J, König-Quartel JM, Guchelaar HJ, Gelderblom H. Marginal increase of sunitinib exposure by grapefruit juice. Cancer Chemother Pharmacol. 2011 Mar;67(3):695-703. PubMed
  140. Goldbart A, Press J, Sofer S, Kapelushnik J. Near fatal acute colchicine intoxication in a child. A case report. Eur J Pediatr. 2000;159(12):895-7. PubMed
  141. Dahan A, Amidon GL. Grapefruit juice and its constituents augment colchicine intestinal absorption: potential hazardous interaction and the role of p-glycoprotein. Pharm Res. 2009 Apr;26(4):883-92. PubMed
  142. Bailey DG. Predicting clinical relevance of grapefruit-drug interactions: a complicated process. J Clin Pharm Ther. 2017 Apr;42(2):125-27. PubMed
  143. Mouly S, Lloret-Linares C, Sellire PO, Sene D, Bergmann JF. Is the clinical relevance of drug-food and drug-herb interactions limited to grapefruit juice and Saint-John's Wort? Pharmacol Res. 2017 Apr;118:82-92. PubMed
  144. Tsuji H, Ohmura K, Nakashima R, et al. Efficacy and safety of grapefruit juice intake accompanying tacrolimus treatment in connective tissues disease patients. Intern Med. 2016;55(12):1547-52.
  145. Jia Y, Liu J, Xu J. Influence of grapefruit juice on pharmacokinetics of triptolide in rats grapefruit juice on the effects of triptolide. Xenobiotica. 2017 Apr 16:1-5. PubMed
  146. Kawaguchi-Suzuki M, Nasiri-Kenari N, Shuster J, et al. Effect of low-furanocoumarin hybrid grapefruit juice consumption on midazolam pharmacokinetics. J Clin Pharmacol. 2017 Mar;57(3):305-11. PubMed
  147. Chorin E, Hochstadt A, Granot Y, et al. Grapefruit juice prolongs the QT interval of healthy volunteers and patients with long QT syndrome. Heart Rhythm. 2019. pii: S1547-5271(19)30368-6. PubMed
  148. Ershad M, Cruz MD, Mostafa A, Mckeever R, Vearrier D, Greenberg MI. Opioid toxidrome following grapefruit juice consumption in the setting of methadone maintenance. J Addict Med 2019;[Epub ahead of print]. PubMed
  149. Shen X, Chen F, Wang F, Huang P, Luo W. The effect of grapefruit juice on the pharmacokinetics of tadalafil in rats. Biomed Res Int 2020;2020:1631735. PubMed
  150. Loretz C, Ho MD, Alam N, Mitchell W, Li AP. Application of cryopreserved human intestinal mucosa and cryopreserved human enterocytes in the evaluation of herb-drug interactions: evaluation of CYP3A inhibitory potential of grapefruit juice and commercial f
  151. Holmberg MT, Tornio A, Hyvärinen H, et al. Effect of grapefruit juice on the bioactivation of prasugrel. Br J Clin Pharmacol. 2015;80(1):139-45. PubMed
  152. Guideline on the investigation of drug interactions. CPMP/EWP/560/95/Rev. 1 Corr. 2. European Medicines Agency, 2015. Available at: https://www.ema.europa.eu/en/documents/scientific-guideline/guideline-investigation-drug-interactions-revision-1_en.pdf (As
  153. Cinderella MA, Morell B, Munjal S. Grapefruit Juice Cleanse Mimicking Quetiapine Overdose: Case Report and Review of Literature. J Clin Psychopharmacol 2021;41(6):690-692. PubMed
  154. Long Z, Ruan M, Wu W, Zeng Q, Li Q, Huang Z. The successful combination of grapefruit juice and venetoclax in an unfit acute myeloid leukemia patient with adverse risk: A case report. Front Oncol 2022;12:912696. PubMed
  155. Piscitelli J, Nikanjam M, Capparelli EV, et al. Fexofenadine Plasma Concentrations to Estimate Systemic Exposure in Healthy Adults Using a Limited Sampling Strategy with a Population Pharmacokinetic Approach. Ther Drug Monit 2023;45(4):539-545. PubMed
  156. Abu Dayyih W, Zakaraya Z, Hailat M, et al. The Validation and Determination of Empagliflozin Concentration in the Presence of Grapefruit Juice Using HPLC for Pharmacokinetic Applications. Molecules 2024;29(6):1236. PubMed
  157. Moffid MA, Mostafa EA, Mahmoud ST, Sayed RM. An eco-friendly ultra-performance liquid chromatography-mass spectrometry method for quantification of rivaroxaban and ticagrelor in rat plasma: grapefruit interactions. Bioanalysis 2023;15(22):1327-1341. PubMed

See these in context on the Grapefruit monograph →

Pear 4 references
  1. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  2. Conceição de Oliveira M, Sichieri R, Sanchez Moura A. Weight loss associated with a daily intake of three apples or three pears among overweight women. Nutrition 2003;19:253-6. PubMed
  3. Nieman DC, Gillitt ND, Sha W, et al. Metabolomics-Based Analysis of Banana and Pear Ingestion on Exercise Performance and Recovery. J Proteome Res 2015;14(12):5367-77. doi: 10.1021/acs.jproteome.5b00909. PubMed
  4. Lee HS, Isse T, Kawamoto T, Baik HW, Park JY, Yang M. Effect of Korean pear (Pyrus pyrifolia cv. Shingo) juice on hangover severity following alcohol consumption. Food Chem Toxicol 2013;58:101-6. doi: 10.1016/j.fct.2013.04.007.

See these in context on the Pear monograph →

Elderberry 6 references
  1. Barak V, Halperin T, Kalickman I. The effect of Sambucol, a black elderberry-based, natural product, on the production of human cytokines: I. Inflammatory cytokines. Eur Cytokine Netw 2001;12:290-6..
  2. Elderberry (Sambucus species). The Poison Plant Patch, Novia Scotia Museum, 2007. Available at: http://museum.gov.ns.ca/poison/?section=species&id=117 (Accessed 16 October 2009).
  3. European elder. Canadian Poisonous Plants Information System. Available at: http://www.cbif.gc.ca/pls/pp/ppack.jump?p_null=all&p_psn=121&p_type=all&p_sci=comm&p_x=px (Accessed 16 October 2009).
  4. Raus K, Pleschka S, Klein P, Schoop R, Fisher P. Effect of an echinacea-based hot drink versus oseltamivir in Influenza treatment: a randomized, double-blind, double-dummy, multicenter, noninferiority clinical trial. . Curr Ther Res Clin Exp. 2015;20;77:6 PubMed
  5. Ramachandran A, Antala D, Pudasainee P, Panginikkod S, Gupta H. A Plausible Association Between the Use of Elderberry and Autoimmune Hepatitis. Cureus 2022;14(4):e24250. PubMed
  6. Agarwal N, Mangla A. Elderberry interaction with pazopanib in a patient with soft-tissue sarcoma: A case report and literature review. Mol Clin Oncol 2024;20(5):36. PubMed

See these in context on the Elderberry monograph →

Sweet Cherry 3 references
  1. Serrano M, Guillen F, Martinez-Romero D, et al. Chemical constiuents and antioxidant activity of sweet cherry at different ripening stages. J Agric Food Chem 2005;53:2741-5.
  2. Ballmer-Weber BK, Scheurer S, Fritsche P, et al. Component-resolved diagnosis with recombinant allergens in patients with cherry allergy. J Allergy Clin Immunol 2002;110:167-73. PubMed
  3. Goncalves B, Landbo AK, Knudsen D, et al. Effect of ripeness and postharvest storage on the phenolic profiles of Cherries (Prunus avium L.). J Agric Food Chem 2004;52:523-30.

See these in context on the Sweet Cherry monograph →

Black Currant 6 references
  1. Guivernau M, Meza N, Barja P, Roman O. Clinical and experimental study on the long-term effect of dietary gamma-linolenic acid on plasma lipids, platelet aggregation, thromboxane formation, and prostacyclin production. Prostaglandins Leukot Essent Fatty A PubMed
  2. Fa-lin Z, Zhen-yu W, Yan H, et al. Efficacy of blackcurrant oil soft capsule, a Chinese herbal drug, in hyperlipidemia treatment. Phytother Res 2010;24 Suppl 2:S209-13. PubMed
  3. Holman CP and Bell AF. A trial of evening primrose oil in the treatment of chronic schizophrenia. J Orhtomolecular Psych 1983;12:302-304.
  4. Vaddadi KS. The use of gamma-linolenic acid and linoleic acid to differentiate between temporal lobe epilepsy and schizophrenia. Prostaglandins Med 1981;6(4):375-379. PubMed
  5. Norred, C. L. and Brinker, F. Potential coagulation effects of preoperative complementary and alternative medicines. Alt Ther 2001;7(6):58-67.
  6. Puri BK. The safety of evening primrose oil in epilepsy. Prostaglandins Leukotrienes Essential Fatty Acids 2007;77:101-3. PubMed

See these in context on the Black Currant monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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