Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

Chromium Xtra 400 mcg Ingredients & Drug Interactions

by Sundown Naturals

Chromium Xtra 400 mcg label
See full label image
Tablet Or Pill Category: Other Combinations
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 Chromium Xtra 400 mcg 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

Chromium Xtra 400 mcg is a dietary supplement by Sundown Naturals with 5 active ingredients. Its ingredients are commonly taken for blood sugar support in type 2 diabetes, weight loss and appetite control, insulin sensitivity.Based on those ingredients, 1,098 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Grapefruit Extract 8:1, Chromium, Inositol. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Chromium Xtra 400 mcg by Sundown Naturals

Ask about any prescription or over-the-counter medication and we check it for interactions with Chromium Xtra 400 mcg by Sundown Naturals — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Chromium Xtra 400 mcg by Sundown Naturals

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 Jul 12, 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 1 of its 5 active ingredients.
  • “Xtra Premium Blend” is a proprietary blend — the label gives one combined amount (402 mg) without saying how much of each component you get.

Chromium Xtra 400 mcg contains five active ingredients. Chromium is the primary nutrient, supplied at 400 micrograms per dose.

It's paired with inositol, a carbohydrate your body makes naturally and uses in cell signaling. Choline bitartrate supports cellular function and is a precursor to acetylcholine, a brain chemical.

Soy lecithin is a phospholipid source often used as an emulsifier, and grapefruit extract (8:1 concentration) rounds out the blend. The tablet also contains inactive ingredients like vegetable cellulose, dicalcium phosphate, silica, and vegetable magnesium stearate as binders and 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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Blood sugar support and chromium supplementation.
  • We looked for evidence on: Chromium deficiency, Diabetes, Impaired glucose tolerance (Prediabetes), Metabolic syndrome, Insulin sensitivity, Glucose metabolism.
  • The strongest evidence on file: Chromium is rated "Likely Effective" for Chromium deficiency (Natural Medicines).
  • Also on file: Inositol is rated "Possibly Effective" for Metabolic syndrome.
  • Also on file: Chromium is rated "Possibly Effective" for Diabetes.

The evidence for these ingredients is mixed and often limited. Chromium is likely effective for chromium deficiency and possibly effective for diabetes support, though possibly ineffective for prediabetes.

Inositol is possibly effective for polycystic ovary syndrome (PCOS) and metabolic syndrome, but possibly ineffective for anxiety and depression. Soy lecithin is likely ineffective for Alzheimer disease, with insufficient evidence for cognitive decline and several other uses.

Choline shows insufficient reliable evidence for most conditions listed, including cognitive decline and Alzheimer disease. Grapefruit extract has insufficient evidence to rate its effectiveness for the conditions studied, including acne, asthma, and upper respiratory infection.

The evidence, ingredient by ingredient Chromium Lecithin Inositol Choline Grapefruit

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients in this product are generally well tolerated at typical doses. Chromium commonly causes mild gastrointestinal irritation, headaches, insomnia, and mood changes; rare serious effects like kidney damage and low platelet counts have been reported with higher doses.

Inositol frequently causes diarrhea, gas, and nausea. Choline can cause a fishy body odor and gastrointestinal upset, especially above 3.5 grams daily.

Soy lecithin may cause abdominal pain, diarrhea, and nausea, and can trigger allergic reactions in people with egg or soy allergies. Grapefruit is generally well tolerated as a whole fruit, but concentrated supplements raise concerns; large amounts may increase arrhythmia risk and possibly raise breast cancer risk in postmenopausal people through effects on estrogen metabolism.

Pregnancy and lactation safety data: chromium is likely safe, inositol is possibly safe in pregnancy, choline is likely safe in both pregnancy and lactation, and soy lecithin is likely safe in pregnancy and lactation. Grapefruit pregnancy and lactation data are not on file.

Side effects, ingredient by ingredient Chromium Lecithin Inositol Choline Grapefruit

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?
  • 4 of the 5 matched ingredients can interact with medications — Inositol, Choline, Chromium, Grapefruit.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications.
  • For scale: 1,099 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.

Before taking this product, double-check if you're on any of these: cyclosporine, scopolamine, amiodarone, buspirone, dextromethorphan, diarrheal medications (terfenadine), celiprolol, etoposide, or other drugs broken down by CYP3A4 enzymes in your liver—grapefruit extract significantly affects all of these. Moderate caution applies to antidiabetes drugs, insulin, levothyroxine (thyroid), and NSAIDs or aspirin due to chromium.

Minor caution with atropine.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This product is primarily a chromium supplement with support ingredients, but grapefruit extract makes it potentially problematic if you take many common medications. If you take heart medications, diabetes drugs, thyroid hormone, immunosuppressants, or any drug metabolized by your liver, talk with your pharmacist before starting.

The chromium and inositol may lower blood sugar, so discuss this if you're on diabetes medication or insulin.

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

Assessment coverage: 5 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 25, 2014.

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 Chromium Xtra 400 mcg, straight from the product label.

Brand Sundown Naturals
Barcode (UPC) 030768009601
Net contents 50 Tablet(s)
Market status On market
Date entered into DSLD Mar 25, 2014
DSLD ID 31641
Product type Other Combinations
Supplement form Tablet Or Pill
Dietary claims / uses Nutrient, All Other
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar 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 Chromium Xtra 400 mcg by Sundown Naturals, 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)
UPC/BARCODE
030768009601
IngredientAmount% DV
Soy Lecithin0 NP--
Inositol0 NP--
Chromium400 mcg333%
Choline Bitartrate0 NP--
Grapefruit Extract 8:10 NP--
Xtra Premium Blend402 mg--

Other ingredients: Vegetable Cellulose, Dicalcium Phosphate, Silica, Vegetable Magnesium Stearate

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.
Formulation

VEGETARIAN FORMULA

No Artificial Color, Flavor or Sweetener, No Preservatives, No Sugar, No Starch, No Milk, No Lactose, No Gluten, No Wheat, No Yeast, No Fish. Sodium Free.

Precautions

WARNING: Not intended for use by pregnant or nursing women. If you are taking any medications or have any medical condition, consult your doctor before use.

KEEP OUT OF REACH OF CHILDREN.

TAMPER RESISTANT: DO NOT USE IF SEAL UNDER CAP IS BROKEN OR MISSING.

Discontinue use and consult your doctor if any adverse reactions occur.

Seals/Symbols

PLEASE RECYCLE

FREE OF Gluten & Wheat

GUARANTEED LABORATORY TESTED QUALITY

General

Prod. No. 44631 07E B44631 EAB

Suggested/Recommended/Usage/Directions

DIRECTIONS: FOR ADULTS, TAKE ONE (1) TABLET DAILY, PREFERABLY WITH A MEAL.

General Statements

As a reminder, discuss the supplements and medications you take with your health care providers.

FDA Statement of Identity

DIETARY SUPPLEMENT

Storage

STORE AT ROOM TEMPERATURE AND AVOID EXCESSIVE HEAT.

Brand IP Statement(s)

(C)2012

Formula

With Inositol and Choline

Smart Facts This advanced formula features the essential mineral Chromium and a special blend featuring Inositol and Choline.

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

See for yourself

Chromium Xtra 400 mcg by Sundown Naturals label

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

Chromium Xtra 400 mcg 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 Chromium Xtra 400 mcg by Sundown Naturals

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill 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.

Chromium

Interacts with
178 drugs
400 mcg per serving Form: Chromium Picolinate

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control i...

Chromium monograph & interactions

Xtra Premium Blend

402 mg per serving

Other (inactive) ingredients: Vegetable Cellulose, Dicalcium Phosphate, Silica, Vegetable Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Chromium Xtra 400 mcg by Sundown Naturals Drug Interactions

Want to check YOUR meds against Chromium Xtra 400 mcg?

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
1,098Drugs
776 Major 215 Moderate 107 Minor

Ingredients driving the most interactions

Grapefruit Extract 8:1 990
Chromium 178
Inositol 86
Choline Bitartrate 16

Individual Drug Interactions

The ingredients in Chromium Xtra 400 mcg interact with 1,098 drugs. Click any drug to see the details.

4 of the 5 ingredients in Chromium Xtra 400 mcg interact with drugs. Each result below shows which ingredient is responsible. Grapefruit Extract 8:1 Chromium Inositol Choline Bitartrate

Each ingredient & the kinds of drugs it affects

For each ingredient in Chromium Xtra 400 mcg 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.

Grapefruit Extract 8:162 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 Extract 8:1 full monograph & all 62 interactions

Chromium5 drug types · 178 drugs

Antidiabetes Drugs

Theoretically, chromium may have additive effects with antidiabetic agents and increase the risk of hypoglycemia.
Some research shows that taking chromium might lower blood glucose levels, especially in patients with poorly controlled type 2 diabetes.

Likelihood Possible Evidence A
Insulin

Theoretically, concomitant use of chromium and insulin might increase the risk of hypoglycemia.
In clinical research, chromium has been shown to increase insulin sensitivity,

Likelihood Possible Evidence B
Levothyroxine (Synthroid, Others)

Chromium might bind levothyroxine in the intestinal tract and decrease levothyroxine absorption.
Clinical research in healthy volunteers shows that taking chromium picolinate 1000 mcg with levothyroxine 1 mg decreases serum levels of levothyroxine by 17% when compared to taking levothyroxine alone. Advise patients to take levothyroxine at least 30 minutes before or 3-4 hours after taking chromium.

Likelihood Probable Evidence B
Aspirin

Theoretically, aspirin might increase chromium absorption.
Animal research suggests that aspirin may increase chromium absorption and chromium levels in the blood.

Likelihood Possible Evidence D
Nonsteroidal Anti-Inflammatory Drugs (Nsaids)

NSAIDs might increase chromium levels in the body.
Drugs that are prostaglandin inhibitors, such as NSAIDs, seem to increase chromium absorption and retention.

Likelihood Possible Evidence D
Chromium full monograph & interactions

Inositol1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking inositol with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research shows that inositol lowers blood glucose levels and glycated hemoglobin (HbA1c) levels in patients with diabetes.

Likelihood Possible Evidence A
Inositol full monograph & interactions

Choline Bitartrate1 drug type · 16 drugs

Atropine

Theoretically, choline might decrease the effects of atropine in the brain.
Animal research shows that administering choline one hour before administering atropine can attenuate atropine-induced decreases in brain levels of acetylcholine. Theoretically, concomitant use of choline and atropine may decrease the effects of atropine.

Likelihood Possible Evidence D
Choline Bitartrate full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Chromium Xtra 400 mcg, from the product label.

Sundown Naturals

See all Sundown Naturals products
Web Address
www.sundownnaturals.com
Pharmacist Counseling Corner

Chromium Xtra 400 mcg by Sundown Naturals: Common Questions

Does Chromium Xtra 400 mcg by Sundown Naturals interact with any medications?
Yes. Based on its ingredients, Chromium Xtra 400 mcg has a known interaction with 1,098 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?
Chromium Xtra 400 mcg contains 5 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.
What does chromium actually do in my body?
Chromium is a mineral that helps regulate blood sugar by improving how insulin works. This product supplies 400 micrograms, which is used mainly for chromium deficiency and possibly to help with diabetes support, though it won't replace your diabetes medication.
Why is grapefruit extract in a supplement if it interacts with so many drugs?
Grapefruit extract is included as a supporting ingredient, likely for its nutrient content. However, because it blocks how your liver processes many medications, it poses real risks if you're on certain drugs. Talk to your pharmacist about whether this product is right for you given your prescriptions.
Does this supplement work for weight loss or blood sugar control?
Chromium is possibly effective for diabetes support, but there's no evidence in the data we hold that this supplement is effective for weight loss. If you're hoping to manage blood sugar, it's a support tool only—your diabetes medication and lifestyle remain your foundation.
Will this give me the fishy-smelling body odor I've heard about with choline?
The choline bitartrate in this product is at a low dose relative to the high-dose supplements that commonly cause fishy body odor. Side effects are unlikely at this dose, though it's possible some people might notice it.
Is it safe to take if I'm pregnant or breastfeeding?
Chromium, choline, and soy lecithin are likely safe during pregnancy and lactation. Inositol is possibly safe in pregnancy but only under medical supervision since full safety isn't established. Talk to your doctor or midwife before starting, especially since you may already be getting these nutrients from your prenatal vitamin.
What's the 'Xtra Premium Blend' listed on the label?
That's the product name for the combined ingredient blend. The individual active ingredients—chromium, inositol, choline, soy lecithin, and grapefruit extract—are what actually do the work; the blend is just how they're packaged together.

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.

Chromium Xtra 400 mcg label
Go deeper

The Full Monographs Behind Chromium Xtra 400 mcg’s Ingredients

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

Herb & supplement monograph

Chromium

Interacts with 178 drugs

Chromium is an essential trace mineral involved in how the body handles sugar and fat. Some studies suggest it may modestly help blood sugar control in certain people with type 2 diabetes, b...

Read the full Chromium monograph → Herb & supplement monograph

Lecithin

Lecithin is a natural fatty substance found in foods and made by the body that is widely used as a supplement and food emulsifier. Evidence supporting most of its health claims is limited, t...

Read the full Lecithin monograph → Herb & supplement monograph

Inositol

Interacts with 86 drugs

Inositol is a sugar alcohol made naturally in the body and found in many foods, and it is sold as a supplement (often myo-inositol) mainly for PCOS, mood, and metabolic concerns. The stronge...

Read the full Inositol monograph → Herb & supplement monograph

Choline

Interacts with 16 drugs

Choline is an essential nutrient your body needs for liver function, brain health, and nerve signaling, and many people get enough from foods like eggs, meat, and fish. Supplements may help...

Read the full Choline 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 →
Sources

Sources & How We Checked

Chromium Xtra 400 mcg'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 247 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.

Lecithin 9 references
  1. Buchman AL, Dubin M, Jenden D, et al. Lecithin increases plasma free choline and decreases hepatic steatosis in long-term total parenteral nutrition patients. Gastroenterology 1992;102:1363-70.
  2. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  3. Chatellier G, Lacomblez L. Tacrine (tetrahydroaminoacridine; THA) and lecithin in senile dementia of the Alzheimer type: a multicentre trial. Groupe Francais d'Etude de la Tetrahydroaminoacridine. BMJ 1990;300:495-9.
  4. Gelenberg AJ, Dorer DJ, Wojcik JD, et al. A crossover study of lecithin treatment of tardive dyskinesia. J Clin Psychiatry 1990;51:149-53.
  5. Little A, Levy R, Chuaqui-Kidd P, Hand D. A double-blind, placebo controlled trial of high-dose lecithin in Alzheimer's disease. J Neurol Neurosurg Psychiatry 1985;48:736-42. PubMed
  6. Palm M, Moneret-Vautrin DA, Kanny G, et al. Food allergy to egg and soy lecithins. Allergy 1999;54:1116-7. PubMed
  7. Drachman DA, Glosser G, Fleming P, et al. Memory decline in the aged: treatment with lecithin and physostigmine. Neurology 1982;32:944-50. PubMed
  8. Gelenberg, A. J., Doller-Wojcik, J. C., and Growdon, J. H. Choline and lecithin in the treatment of tardive dyskinesia: preliminary results from a pilot study. Am J Psychiatry 1979;136(6):772-776. PubMed
  9. Electronic Code of Federal Regulations. Title 21, Chapter 1, Subchapter B, Part 184: Direct food substances affirmed as Generally Recognized as Safe. Subpart B - listing of specific substances affirmed as GRAS. Sec. 184.1400 Lecithin. Available at: https:

See these in context on the Lecithin monograph →

Inositol 14 references
  1. Palatnik A, Frolov K, Fux M, Benjamin J. Double-blind, controlled, crossover trial of inositol versus fluvoxamine for the treatment of panic disorder. J Clin Psychopharmacol 2001;21:335-9.. PubMed
  2. Allan SJ, Kavanagh GM, Herd RM, Savin JA. The effect of inositol supplements on the psoriasis of patients taking lithium: a randomized, placebo-controlled trial. Br J Dermatol 2004;150:966-9. PubMed
  3. Machado-Vieira R, Viale CI, Kapczinski F. Mania associated with an energy drink: the possible role of caffeine, taurine, and inositol. Can J Psychiatry 2001;46:454-5. PubMed
  4. Kamenov Z, Kolarov G, Gateva A, Carlomagno G, Genazzani AD. Ovulation induction with myo-inositol alone and in combination with clomiphene citrate in polycystic ovarian syndrome patients with insulin resistance. Gynecol Endocrinol 2015;31(2):131-5. PubMed
  5. Matarrelli B, Vitacolonna E, D'Angelo M, et al. Effect of dietary myo-inositol supplementation in pregnancy on the incidence of maternal gestational diabetes mellitus and fetal outcomes: a randomized controlled trial. J Matern Fetal Neonatal Med 2013;26(1 PubMed
  6. Mukai T, Kishi T, Matsuda Y, Iwata N. A meta-analysis of inositol for depression and anxiety disorders. Hum Psychopharmacol 2014;29(1):55-63. PubMed
  7. Farren M, Daly N, McKeating A, Kinsley B, Turner MJ, Daly S. The Prevention of Gestational Diabetes Mellitus With Antenatal Oral Inositol Supplementation: A Randomized Controlled Trial. Diabetes Care. 2017;40(6):759-63. PubMed
  8. Zheng X, Liu Z, Zhang Y, et al. Relationship Between Myo-Inositol Supplementary and Gestational Diabetes Mellitus: A Meta-Analysis. Medicine (Baltimore). 2015;94(42):e1604. PubMed
  9. Crawford TJ, Crowther CA, Alsweiler J, Brown J. Antenatal dietary supplementation with myo-inositol in women during pregnancy for preventing gestational diabetes. Cochrane Database Syst Rev. 2015;(12):CD011507. PubMed
  10. Maurizi AR, Menduni M, Del Toro R, et al. A pilot study of D-chiro-inositol plus folic acid in overweight patients with type 1 diabetes. Acta Diabetol. 2017;54(4):361-65. PubMed
  11. Leppink EW, Redden SA, Grant JE. A double-blind, placebo-controlled study of inositol in trichotillomania. Int Clin Psychopharmacol. 2017;32(2):107-14. PubMed
  12. Lam S, Mandrekar SJ, Gesthalter Y. A Randomized Phase IIb Trial of myo-Inositol in Smokers with Bronchial Dysplasia. Cancer Prev Res (Phila). 2016;9(12):906-14.
  13. Wozniak J, Faraone SV, Chan J, et al. A randomized clinical trial of high eicosapentaenoic acid omega-3 fatty acids and inositol as monotherapy and in combination in the treatment of pediatric bipolar spectrum disorders: a pilot study. J Clin Psychiatry. PubMed
  14. Vitale SG, Corrado F, Caruso S, et al. Myo-inositol supplementation to prevent gestational diabetes in overweight non-obese women: bioelectrical impedance analysis, metabolic aspects, obstetric and neonatal outcomes - a randomized and open-label, placebo-

See these in context on the Inositol monograph →

Chromium 53 references
  1. Cerulli J, Grabe DW, Gauthier I, et al. Chromium picolinate toxicity. Ann Pharmacother 1998;32:428-31. PubMed
  2. Urberg M, Zemel MB. Evidence for synergism between chromium and nicotinic acid in the control of glucose tolerance in elderly humans. Metabolism 1987;36:896-9. PubMed
  3. Mohamedshah FY, Moser-Veillon PB, Yamini S, et al. Distribution of a stable isotope of chromium (53Cr) in serum, urine, and breast milk in lactating women. Am J Clin Nutr 1998;67:1250-5. PubMed
  4. Wasser WG, Feldman NS, D'Agati VD. Chronic renal failure after ingestion of over-the-counter chromium picolinate. [letter]. Ann Intern Med 1997;126:410. PubMed
  5. Mertz W. Interaction of chromium with insulin: a progress report. Nutr Rev 1998;56:174-7. PubMed
  6. Anderson RA. Chromium, glucose intolerance and diabetes. J Am Coll Nutr 1998;17:548-55. PubMed
  7. McLeod MN, Gaynes BN, Golden RN. Chromium potentiation of antidepressant pharmacotherapy for dysthymic disorder in 5 patients. J Clin Psych 1999;60:237-40. PubMed
  8. Fowler JF Jr. Systemic contact dermatitis caused by oral chromium picolinate. Cutis 2000;65:116. DOI
  9. Trent LK, Thieding-Cancel D. Effects of chromium picolinate on body composition. J Sports Med Phys Fitness 1995;35:273-80.
  10. 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.
  11. Rabinovitz H, Friedensohn A, Leibovitz A, et al. Effect of chromium supplementation on blood glucose and lipid levels in type 2 diabetes mellitus elderly patients. Int J Vitam Nutr Res 2004;74:178-82. PubMed
  12. Lanca S, Alves A, Vieira AI, et al. Chromium-induced toxic hepatitis. Eur J Intern Med 2002;13:518-20. PubMed
  13. Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.. PubMed
  14. Davidson JR, Abraham K, Connor KM, McLeod MN. Effectiveness of chromium in atypical depression: a placebo-controlled trial. Biol Psychiatry 2003;53:261-4.. PubMed
  15. Food Standards Agency. Medicines and Healthcare products Regulatory Agency (MHRA). Expert Group on Vitamins and Minerals. Available at: http://cot.food.gov.uk/sites/default/files/vitmin2003.pdf.
  16. Mouser JF, Hak EB, Helms RA, et al. Chromium and zinc concentrations in pediatric patients receiving long-term parenteral nutrition. Am J Health Syst Pharm 1999;56:1950-6. PubMed
  17. Stevens T, Qadri A, Zein NN. Two patients with acute liver injury associated with use of the herbal weight-loss supplement hydroxycut. Ann Intern Med 2005;142:477-8. PubMed
  18. Wani S, Weskamp C, Marple J, Spry L. Acute tubular necrosis associated with chromium picolinate-containing dietary supplement. Ann Pharmacother 2006;40:563-6. PubMed
  19. Kleefstra N, Houweling ST, Jansman FG, et al. Chromium treatment has no effect in patients with poorly controlled, insulin-treated type 2 diabetes in an obese Western population: a randomized, double-blind, placebo-controlled trial. Diabetes Care 2006;29: PubMed
  20. Martin J, Wang ZQ, Zhang XH, et al. Chromium picolinate supplementation attenuates body weight gain and increases insulin sensitivity in subjects with type 2 diabetes. Diabetes Care 2006;29:1826-32. PubMed
  21. Singer GM, Geohas J. The effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial. Diabetes Technol Ther 2006;8:636-43. PubMed
  22. John-Kalarickal J, Pearlman G, Carlson HE. New medications which decrease levothyroxine absorption. Thyroid 2007;17:763-5. PubMed
  23. Yazaki Y, Faridi Z, Ma Y, et al. A pilot study of chromium picolinate for weight loss. J Altern Complement Med 2010;16:291-9. PubMed
  24. Davis ML, Seaborn CD, and Stoecker BJ. Effects of over-the-counter drugs on chromium retention and urinary excretion in rats. Nutrition Research 1995;15(2):201-210.
  25. Young P, Turiansky G, Bonner M, and et al. Acute generalized exanthematous pustulosis induced by chromium picolinate. J.Am Acad.Dermatol. 1999;41(5 Pt 2):820-823. PubMed
  26. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Lung cancer among workers in chromium chemical production. Am J Ind.Med 2000;38(2):115-126. DOI
  27. Gibb, H. J., Lees, P. S., Pinsky, P. F., and Rooney, B. C. Clinical findings of irritation among chromium chemical production workers. Am J Ind.Med 2000;38(2):127-131. PubMed
  28. Pittler, M. H. and Ernst, E. Dietary supplements for body-weight reduction: a systematic review. Am.J.Clin Nutr. 2004;79(4):529-536. PubMed
  29. Pei, D., Hsieh, C. H., Hung, Y. J., Li, J. C., Lee, C. H., and Kuo, S. W. The influence of chromium chloride-containing milk to glycemic control of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial. Metabolism 2 PubMed
  30. Hisatomi, K., Ishii, H., Hashiguchi, K., Seki, M., Ide, M., Sugiyama, K., Ishimoto, H., Nakayama, S., Mukae, H., and Kohno, S. Interstitial pneumonia caused by inhalation of fumes of nickel and chrome. Respirology. 2006;11(6):814-817. PubMed
  31. Kleefstra, N., Houweling, S. T., Bakker, S. J., Verhoeven, S., Gans, R. O., Meyboom-de Jong, B., and Bilo, H. J. Chromium treatment has no effect in patients with type 2 diabetes in a Western population: a randomized, double-blind, placebo-controlled tri DOI
  32. Parsons, A., Ingram, J., Inglis, J., Aveyard, P., Johnstone, E., Brown, K., Franklin, M., and Bermudez, I. A proof of concept randomised placebo controlled factorial trial to examine the efficacy of St John's wort for smoking cessation and chromium to pr
  33. Bagdon RE and Hazen RE. Skin permeation and cutaneous hypersensitivity as a basis for making risk assessments of chromium as a soil contaminant. Environ.Health Perspect. 1991;92:111-119. PubMed
  34. Bharmal, S. V., Moyes, V., Ahmed, S., and Grossman, A. Hypoglycaemia: possible mediation by chromium salt medication. Hormones.(Athens.) 2010;9(2):181-183. PubMed
  35. Krol, E., Krejpcio, Z., Byks, H., Bogdanski, P., and Pupek-Musialik, D. Effects of chromium brewer's yeast supplementation on body mass, blood carbohydrates, and lipids and minerals in type 2 diabetic patients. Biol.Trace Elem.Res. 2011;143(2):726-737.
  36. Unisa, S., Jagannath, P., Dhir, V., Khandelwal, C., Sarangi, L., and Roy, T. K. Population-based study to estimate prevalence and determine risk factors of gallbladder diseases in the rural Gangetic basin of North India. HPB (Oxford) 2011;13(2):117-125. PubMed
  37. Noda, S., Asano, Y., and Sato, S. Lichen planus in a patient with long-term exposure to chrome. Eur.J.Dermatol. 2011;21(3):417-418. PubMed
  38. Xiang, J., Sun, Z., and Huan, J. N. Intensive chromic acid burns and acute chromium poisoning with acute renal failure. Chin Med.J.(Engl.) 7-5-2011;124(13):2071-2073.
  39. Chhabra, D., Oda, K., Jagannath, P., Utsunomiya, H., Takekoshi, S., and Nimura, Y. Chronic heavy metal exposure and gallbladder cancer risk in India, a comparative study with Japan. Asian Pac.J.Cancer Prev. 2012;13(1):187-190. PubMed
  40. Huszonek, J. Over-the-counter chromium picolinate. Am J Psychiatry 1993;150(10):1560-1561. PubMed
  41. Bunner S and McGinnis R. Chromium-induced hypoglycemia. Psychosomatics 1998;39(3):298-299. PubMed
  42. Martin, W. R. and Fuller, R. E. Suspected chromium picolinate-induced rhabdomyolysis. Pharmacotherapy 1998;18(4):860-862. DOI
  43. Proctor, D. M., Fredrick, M. M., Scott, P. K., Paustenbach, D. J., and Finley, B. L. The prevalence of chromium allergy in the United States and its implications for setting soil cleanup: a cost-effectiveness case study. Regul.Toxicol Pharmacol 1998;28(1 PubMed
  44. De Marchi S, Cecchin E, De Marchi SU. Systemic allergic dermatitis resulting from oral administration of chromium with a food supplement. Contact Dermatitis 2014;70(2):123-5. PubMed
  45. Hedberg YS, Gumulka M, Lind ML, Matura M, Lidén C. Severe occupational chromium allergy despite cement legislation. Contact Dermatitis. 2014;70(5):321-3. PubMed
  46. Thyssen JP, Jellesen MS, Møller P, Menné T, Johansen JD. Allergic chromium dermatitis from wearing 'chromium-free' footwear. Contact Dermatitis 2014;70(3):185-7. PubMed
  47. Liu Y, Cotillard A, Vatier C, et al. A Dietary Supplement Containing Cinnamon, Chromium and Carnosine Decreases Fasting Plasma Glucose and Increases Lean Mass in Overweight or Obese Pre-Diabetic Subjects: A Randomized, Placebo-Controlled Trial. PLoS One.
  48. Jamilian M, Asemi Z. Chromium Supplementation and the Effects on Metabolic Status in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Ann Nutr Metab. 2015;67(1):42-8. PubMed
  49. Guimarães MM, Carvalho AC, Silva MS. Effect of chromium supplementation on the glucose homeostasis and anthropometry of type 2 diabetic patients: Double blind, randomized clinical trial: Chromium, glucose homeostasis and anthropometry. J Trace Elem Med Bi PubMed
  50. Paiva AN, Lima JG, Medeiros AC, et al. Beneficial effects of oral chromium picolinate supplementation on glycemic control in patients with type 2 diabetes: A randomized clinical study. J Trace Elem Med Biol. 2015;32:66-72. PubMed
  51. Yin RV, Phung OJ. Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus. Nutr J. 2015;14:14. PubMed
  52. Jamilian M, Zadeh Modarres S, Amiri Siavashani M, et al. The influences of chromium supplementation on glycemic control, markers of cardio-metabolic risk, and oxidative stress in infertile polycystic ovary syndrome women candidate for in vitro fertilizati
  53. Alinaghi F, Thyssen JP, Zachariae C, Johansen JD. No immediate effect of regulatory reduction of chromium in leather among adult patients with chromium allergy. Contact Dermatitis 2021;85(5):514-522. PubMed

See these in context on the Chromium monograph →

Choline 14 references
  1. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  2. Cho E, Willett WC, Colditz GA, et al. Dietary choline and betaine and the risk of distal colorectal adenoma in women. J Natl Cancer Inst 2007;99:1224-31. PubMed
  3. Schmidt, C., Abicht, A., Krampfl, K., Voss, W., Stucka, R., Mildner, G., Petrova, S., Schara, U., Mortier, W., Bufler, J., Huebner, A., and Lochmuller, H. Congenital myasthenic syndrome due to a novel missense mutation in the gene encoding choline acetyl
  4. Tamminga, C., Smith, R. C., Chang, S., Haraszti, J. S., and Davis, J. M. Depression associated with oral choline. Lancet 10-23-1976;2(7991):905. PubMed
  5. Wood, J. L. and Allison, R. G. Effects of consumption of choline and lecithin on neurological and cardiovascular systems. Fed.Proc. 1982;41(14):3015-3021.
  6. Growdon, J. H. and Gelenberg, A. J. Choline and lecithin administration to patients with tardive dyskinesia. Trans.Am.Neurol.Assoc. 1978;103:95-99.
  7. Smith, C. M., Swash, M., Exton-Smith, A. N., Phillips, M. J., Overstall, P. W., Piper, M. E., and Bailey, M. R. Choline therapy in Alzheimer's disease. Lancet 8-5-1978;2(8084):318. PubMed
  8. Morrison, L. M. and W. F. Gonzales. Choline in coronary atherosclerosis. Amer.Heart J. 1950;39:729.
  9. Christie, J. G. Blackburn 1. M. Glen A. I. M. Zeisel S. Shering A. & Yates C. M. Effects of choline and lecithin on CSF choline levels and on cognitive functioning in patients with presenile dementia of the Alzheimer type. Nutrition and the brain 1979;5
  10. Sidhu N, Davies S, Nadarajah A, et al. Oral choline supplementation for postoperative pain. Br J Anaesth 2013;111(2):249-55. PubMed
  11. Wozniak JR, Fuglestad AJ, Eckerle JK, et al. Choline supplementation in children with fetal alcohol spectrum disorders has high feasibility and tolerability. Nutr Res. 2013;33(11):897-904. PubMed
  12. Wozniak JR, Fuglestad AJ, Eckerle JK, et al. Choline supplementation in children with fetal alcohol disorders: a randomized, double-blind, placebo-controlled trial. Am J Clin Nutr. 2015;102(5): 1113-25.
  13. Ross RG, Hunter SK, McCarthy L, et al. Perinatal choline effects on neonatal pathophysiology related to later schizophrenia risk. Am J Psychiatry. 2013;170(3):290-8. PubMed
  14. Food and Nutrition Board, Institute of Medicine. Choline. Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B-6, Vitamin B-12, Pantothenic Acid, Biotin, and Choline. Washington D.C.: National Academy Press; 1998:390-422.

See these in context on the Choline monograph →

Grapefruit 157 references
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  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
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  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.
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  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
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  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
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  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
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  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
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  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 →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

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