Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Hair Multivitamin Ingredients & Drug Interactions

by California Gold Nutrition

Hair Multivitamin label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Oct 7, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Hair Multivitamin 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: Moderate

Hair Multivitamin is a dietary supplement by California Gold Nutrition with 15 active ingredients. Its ingredients are commonly taken for morning sickness in pregnancy, premenstrual syndrome (pms), preventing or treating b6 deficiency.Based on those ingredients, 732 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Evening Primrose Oil, Vitamin B6, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Hair Multivitamin by California Gold Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Hair Multivitamin by California Gold Nutrition — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Hair Multivitamin by California Gold Nutrition

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 6, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 15 of its 15 active ingredients.
  • “Folate” is listed as a grouped ingredient — the label gives one combined amount (680 mcg DFE) without saying how much of each component you get.

Hair Multivitamin contains 15 active ingredients chosen to support hair health. The formula includes B vitamins—vitamin B6, folic acid, thiamine, riboflavin, and pantothenic acid—which play roles in energy metabolism and cell function.

You'll also find vitamin C, an antioxidant; the amino acids L-methionine, L-cysteine, and L-lysine; minerals including zinc and copper; and biotin, a B vitamin often associated with hair and skin support. The formula rounds out with hyaluronic acid and hydrolyzed collagen (collagen peptides), which some people use for skin hydration and elasticity, plus evening primrose oil for its fatty acid content.

The capsules also contain inactive ingredients—gelatin, sugar, polyvinylpyrrolidone, starch, silicon dioxide, and microcrystalline cellulose—which serve as fillers, binders, and capsule material.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Supports healthy hair.
  • We looked for evidence on: Androgenic alopecia, Alopecia areata, Aging skin, Hair loss, Hair thinning, Hair growth.
  • The strongest evidence on file: Collagen Peptides is rated "Possibly Effective" for Aging skin (Natural Medicines).
  • Also on file: Zinc is rated "Possibly Ineffective" for Alopecia areata.
  • Also on file: Methionine is rated "Insufficient Reliable Evidence To Rate" for Androgenic alopecia.

The effectiveness ratings in our data are mixed and vary widely by ingredient and claimed use. For hair specifically, we don't hold effectiveness data.

However, individual ingredients have been studied for related purposes: biotin shows possibly ineffective evidence for alopecia areata and seborrheic dermatitis; L-lysine shows possibly effective evidence for cold sores but insufficient evidence for pressure or diabetic ulcers; zinc is possibly effective for acne and age-related macular degeneration; and hydrolyzed collagen is possibly effective for aging and dry skin. Vitamin C, vitamin B6, folic acid, and copper each have various ratings for different health conditions (deficiencies, anemia, birth defects, cardiovascular support), but none of these speak directly to hair growth or quality.

The evidence supporting this product's use specifically for hair is not established in the data we hold.

The evidence, ingredient by ingredient Vitamin B6 Biotin Methionine Vitamin C Thiamine Folic Acid L-cysteine Copper

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 14 of the 15 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 15 of 15.
  • General safety write-ups exist for 15 of 15.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients are generally well tolerated at recommended supplement doses. However, some carry cautions.

Vitamin B6 is safe at normal amounts but high doses over time can cause nerve damage (sensory neuropathy), especially at very high daily intakes. Folic acid is generally safe at standard doses but very high doses can cause sleep disturbances, confusion, and other neurological effects; it's also recommended during pregnancy at prenatal doses to prevent birth defects.

Vitamin C is well tolerated but high doses above 2 grams daily can cause kidney stones (especially in susceptible people) and GI upset. Zinc is safe below 40 mg daily for adults but excess can contribute to copper deficiency.

Evening primrose oil is generally tolerated short-term but long-term safety data are limited, and it's best avoided in pregnancy unless directed by your doctor. L-cysteine, L-methionine, and biotin have limited long-term safety data at supplement doses, so medical guidance is advised before high-dose use.

Hyaluronic acid and hydrolyzed collagen have insufficient pregnancy and lactation safety data; for hyaluronic acid specifically, oral supplement safety is not fully studied.

Side effects, ingredient by ingredient Vitamin B6 Biotin Methionine Vitamin C Thiamine Folic Acid L-cysteine Copper

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 10 of the 15 matched ingredients can interact with medications — Lysine, Copper, Vitamin B6, Riboflavin, Thiamine, among others.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; diabetes medications; lithium; Parkinson's medications.
  • For scale: 732 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 the following medication types with your doctor or pharmacist: seizure medications (phenobarbital, phenytoin, primidone)—folic acid may worsen seizure control; blood pressure medications—vitamin B6 may have additive effects; blood thinners including warfarin and antiplatelet drugs—vitamin C at high doses and evening primrose oil may interfere; antibiotics including quinolones, tetracyclines, and cephalexin—zinc may reduce their absorption; oral contraceptives and hormone therapy—vitamin C may increase estrogen levels; chemotherapy drugs (capecitabine, methotrexate, 5-fluorouracil, alkylating agents, antitumor antibiotics)—folic acid and vitamin C may reduce effectiveness or increase toxicity; HIV medications including integrase inhibitors and ritonavir-based regimens—zinc may lower levels; lithium—evening primrose oil may reduce levels; and antidiabetes drugs—L-cysteine may theoretically increase hypoglycemia risk.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Hair Multivitamin is a nutrient-dense formula with ingredients that support various aspects of metabolism and tissue health, though its specific effectiveness for hair is not documented in our data. If you take any prescription medications—especially blood pressure drugs, seizure medications, anticoagulants, antibiotics, chemotherapy, lithium, or HIV drugs—check your exact medications with the tool on this page before starting.

Talk with your doctor or pharmacist about whether this product is right for you and whether the dose is appropriate, especially if you're pregnant, breastfeeding, or managing a chronic condition.

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

Assessment coverage: 15 of 15 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 14, 2023.

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 Hair Multivitamin, straight from the product label.

Brand California Gold Nutrition
Barcode (UPC) 898220019151
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Dec 14, 2023
DSLD ID 299620
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy 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 Hair Multivitamin by California Gold Nutrition, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
45
UPC/BARCODE
898220019151
IngredientAmount% DV
Vitamin B65.1 mg300%
Folic Acid400 mcg--
Biotin5000 mcg16667%
L-Methionine10 mg--
Vitamin C90 mg100%
Thiamine6 mg500%
Folate680 mcg DFE170%
L-Cysteine10 mg--
Copper2.7 mg300%
Zinc5.5 mg50%
Pantothenic Acid5 mg100%
L-Lysine10 mg--
Riboflavin6.5 mg500%
Hyaluronic Acid1 mg--
Hydrolyzed Collagen100 mg--
Evening Primrose Oil880 mg--

Other ingredients: Gelatin, Sugar, Polyvinylpyrrolidone, Starch, Silicon Dioxide, Microcrystalline Cellulose

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.
Suggested/Recommended/Usage/Directions

Suggested use: Take 2 capsules daily, with food. Best when taken as directed by a qualified healthcare professional.

Precautions

Warnings: Keep out of reach of children.

Pregnant or lactating women, the chronically ill, elderly, individuals under the age of 18, those taking prescription medications (e.g., blood thinners) as well as those with a physician-diagnosed medical condition should consult with a physician, pharmacist, naturopath or other qualified healthcare professional prior to taking dietary supplements.

Pregnant or lactating women, the chronically ill, elderly, individuals under the age of 18, those taking prescription medications (e.g., blood thinners) as well as those with a physician-diagnosed medical condition should consult with a physician, pharmacist, naturopath or other qualified healthcare professional prior to taking dietary supplements.

Sealed for your protection. Do not use seal is missing or broken.

Not manufactured with milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soy, sesame, or gluten. Produced in an FDA-registered, third-party audited, and cGMP-compliant facility that may process other products that contain these allergens or ingredients.

Storage

Store in a cool, dry place. Protect from heat, light, and moisture.

Brand IP Statement(s)

California Gold Nutrition is a registered trademark of Madre Labs, LLC

Formulation

Supports healthy hair

Formulated without: Gluten GMOs Soy

Beadlets in capsules

Not manufactured with milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soy, sesame, or gluten.

FDA Statement of Identity

Dietary Supplement

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

See for yourself

Hair Multivitamin by California Gold Nutrition label

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

Hair Multivitamin 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 Hair Multivitamin by California Gold Nutrition

These are the 15 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container45 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.

Vitamin B6

Interacts with
210 drugs
5.1 mg per serving Form: Pyridoxine Hydrochloride

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & interactions

Biotin

No known
interactions
5000 mcg per serving

Biotin (vitamin B7) is a water-soluble vitamin your body needs to turn food into energy and to support healthy hair, skin, and nails. Most people get...

Biotin monograph & interactions

L-Methionine

No known
interactions
10 mg per serving

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a norma...

L-Methionine monograph & interactions

Vitamin C

Interacts with
207 drugs
90 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

Thiamine

Interacts with
3 drugs
6 mg per serving Form: Thiamine Mononitrate

Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get eno...

Thiamine monograph & interactions

Folate

680 mcg DFE per serving

L-Cysteine

Interacts with
86 drugs
10 mg per serving

L-cysteine is a sulfur-containing amino acid your body uses to make proteins and the antioxidant glutathione. Most people get enough from food, and su...

L-Cysteine monograph & interactions

Copper

Interacts with
31 drugs
2.7 mg per serving Form: Cupric Oxide

Copper is an essential trace mineral your body needs in small amounts for making red blood cells, supporting nerves and bones, and helping enzymes wor...

Copper monograph & interactions

Zinc

Interacts with
67 drugs
5.5 mg per serving Form: Zinc Sulfate

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

Pantothenic Acid

No known
interactions
5 mg per serving Form: D-Calcium Pantothenate

Pantothenic acid is vitamin B5, an essential nutrient your body uses to turn food into energy. True deficiency is very rare because it is found in nea...

Pantothenic Acid monograph & interactions

L-Lysine

Interacts with
1 drug
10 mg per serving Form: L-Lysine Hydrochloride

Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to t...

L-Lysine monograph & interactions

Riboflavin

Interacts with
20 drugs
6.5 mg per serving

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally...

Riboflavin monograph & interactions

Hyaluronic Acid

No known
interactions
1 mg per serving Form: Sodium Hyaluronate

Hyaluronic acid is a natural substance in the body that helps hold water in the skin, joints, and eyes. Oral and topical products are popular for skin...

Hyaluronic Acid monograph & interactions

Hydrolyzed Collagen

No known
interactions
100 mg per serving

Collagen peptides are a well-absorbed form of protein that may modestly improve skin elasticity and joint comfort for some people, though evidence is...

Hydrolyzed Collagen monograph & interactions

Evening Primrose Oil

Interacts with
234 drugs
880 mg per serving Form: Gamma-Linolenic Acid

Evening primrose oil is a seed oil rich in gamma-linolenic acid (GLA), an omega-6 fatty acid, that is popularly used for skin conditions, PMS, and bre...

Evening Primrose Oil monograph & interactions

Other (inactive) ingredients: Gelatin, Sugar, Polyvinylpyrrolidone, Starch, Silicon Dioxide, Microcrystalline Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Hair Multivitamin by California Gold Nutrition Drug Interactions

Want to check YOUR meds against Hair Multivitamin?

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
732Drugs
586 Moderate 146 Minor

Ingredients driving the most interactions

Evening Primrose Oil 234
Vitamin B6 210
Vitamin C 207
L-Cysteine 86
Zinc 67

Individual Drug Interactions

The ingredients in Hair Multivitamin interact with 732 drugs. Click any drug to see the details.

10 of the 15 ingredients in Hair Multivitamin interact with drugs. Each result below shows which ingredient is responsible. Evening Primrose Oil Vitamin B6 Vitamin C L-Cysteine Zinc Folic Acid Copper Riboflavin Thiamine L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in Hair Multivitamin 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.

Evening Primrose Oil5 drug types · 234 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Evening primrose oil contains gamma linolenic acid (GLA). There is preliminary clinical evidence that GLA can reduce platelet aggregation and prolong bleeding time.

Likelihood Possible Evidence D
Lithium

Theoretically, concomitant use of lithium with evening primrose oil might decrease lithium levels and effects.
In a case report, a patient on a stable dose of lithium for 10 years experienced a reduction in lithium levels after taking evening primrose oil 500 mg daily. Baseline levels were 0.69 mmol/L, which decreased to 0.37 mmol/L after 2 months and 0.23 mmol/L after 3 months of use. Lithium levels increased within 6 weeks of discontinuing evening primrose oil, to 0.73 mmol/L; no clinical effects were noted.

Likelihood Possible Evidence D
Lopinavir/Ritonavir (Kaletra)

Theoretically, evening primrose oil might increase the levels and effects of lopinavir.
In a case report, an HIV patient who took evening primrose oil (Efamol) along with lopinavir/ritonavir experienced an increase in serum levels of lopinavir to 15.2 mg/L. Six weeks after discontinuing evening primrose oil, levels of lopinavir returned to the normal range of 5-10 mg/L. When re-challenged with evening primrose oil for a week, the patient's lopinavir levels increased from 6.69 to 8.11 mg/L. It is suspected that evening primrose oil increases levels of lopinavir by inhibiting cytochrome P450 3A4 (CYP3A4), which metabolizes lopinavir. However, this effect has not been reported in other research.

Likelihood Possible Evidence D
Phenothiazines

Theoretically, taking evening primrose oil with phenothiazines might increase the risk of convulsions.
Evening primrose 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. 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 oil 4 grams daily was added. One of these patients had a prior history of seizures. It is unclear whether evening primrose oil had any additive epileptogenic effects with the phenothiazines; there is no evidence that taking evening primrose oil alone causes seizures.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
In vitro research shows that linoleic acid, a constituent of evening primrose oil, inhibits CYP2C9.

Likelihood Possible Evidence D
Evening Primrose Oil full monograph & interactions

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D
Vitamin B6 full monograph & 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

L-Cysteine1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking L-cysteine supplements with antidiabetes drugs might increase the risk of hypoglycemia.
Animal research suggests that L-cysteine can have hypoglycemic effects.

Likelihood Possible Evidence D
L-Cysteine 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

Folic Acid7 drug types · 40 drugs

5-Fluorouracil

Theoretically, high doses of folic acid might increase the toxicity of 5-fluorouracil.
Increases in gastrointestinal side effects of 5-fluorouracil, such as stomatitis and diarrhea, have been described in two clinical studies when leucovorin, a form of folic acid, was administered with 5-fluorouracil.

Likelihood Possible Evidence D
Capecitabine (Xeloda)

Use of high-dose folic acid might contribute to capecitabine toxicity.
Clinical research suggests that higher serum folate levels are associated with an increased risk for moderate or severe toxicity during capecitabine-based treatment for colorectal cancer. Additionally, in one case report, taking folic acid 15 mg daily might have contributed to increased toxicity, including severe diarrhea, vomiting, edema, hand-foot syndrome, and eventually death, in a patient prescribed capecitabine.

Likelihood Possible Evidence D
Methotrexate (Trexall, Others)

Folic acid might reduce the efficacy of methotrexate as a cancer treatment when given concurrently.
Methotrexate exerts its cytotoxic effects by preventing conversion of folic acid to the active form needed by cells. There is some evidence that folic acid supplements reduce the efficacy of methotrexate in the treatment of acute lymphoblastic leukemia, and theoretically they could reduce its efficacy in the treatment of other cancers. Advise cancer patients to consult their oncologist before using folic acid supplements. In patients treated with long-term, low-dose methotrexate for rheumatoid arthritis (RA) or psoriasis, folic acid supplements can reduce the incidence of side effects, without reducing efficacy.

Likelihood Probable Evidence B
Phenobarbital (Luminal)

Folic acid might have antagonistic effects on phenobarbital and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of phenobarbital and worsening seizure control. Monitor closely for increased seizure activity.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Folic acid might reduce serum levels of phenytoin in some patients.
Folic acid may be a cofactor in phenytoin metabolism. Folic acid, in doses of 1 mg daily or more, can reduce serum levels of phenytoin in some patients. Increases in seizure frequency have been reported. If folic acid supplements are added to established phenytoin therapy, monitor serum phenytoin levels closely. If phenytoin and folic acid are started at the same time and continued together, adverse changes in phenytoin pharmacokinetics are avoided. Note that phenytoin also reduces serum folate levels.

Likelihood Probable Evidence B
Primidone (Mysoline)

Folic acid might have antagonistic effects on primidone and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of primidone and worsening seizure control. Monitor closely for increased seizure activity. Note that primidone also reduces serum folate levels.

Likelihood Probable Evidence B
Pyrimethamine (Daraprim)

Folic acid might antagonize the effects of pyrimethamine.
Folic acid can antagonize the antiparasitic effects of pyrimethamine against toxoplasmosis and Pneumocystis carinii pneumonia. Folic acid doesn't antagonize the effects of pyrimethamine in the treatment of malaria, because malarial parasites cannot use exogenous folic acid. Use folinic acid as an alternative to folic acid when indicated.

Likelihood Probable Evidence D
Folic Acid full monograph & interactions

Copper2 drug types · 31 drugs

Penicillamine (Cuprimine, Depen)

Theoretically, taking copper with penicillamine might decrease the absorption of penicillamine; separate dosing by at least 2 hours.
Copper chelates penicillamine, which decreases its absorption and may reduce its clinical effects.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking copper with contraceptive drugs might increase the levels and toxic effects of copper.
A meta-analysis of clinical studies suggests that chronic use of oral contraceptives increases serum copper levels by a mean of 57 mcg/dL. In most people, this resulted in levels above the normal reference range for copper.

Likelihood Possible Evidence D
Copper full monograph & interactions

Riboflavin1 drug type · 20 drugs

Tetracycline Antibiotics

Theoretically, taking riboflavin with tetracycline antibiotics may decrease the potency of these antibiotics.
In vitro research suggests that riboflavin may inhibit the potency of tetracycline antibiotics. It is not clear if this effect is clinically significant, as this interaction has not been reported in humans.

Likelihood Possible Evidence D
Riboflavin full monograph & interactions

Thiamine1 drug type · 3 drugs

Trimethoprim (Proloprim)

Trimethoprim might increase blood levels of thiamine.
In vitro, animal, and clinical research suggest that trimethoprim inhibits intestinal thiamine transporter ThTR-2, hepatic transporter OCT1, and renal transporters OCT2, MATE1, and MATE2, resulting in paradoxically increased thiamine plasma concentrations.

Likelihood Probable Evidence B
Thiamine full monograph & interactions

L-Lysine1 drug type · 1 drug

5-Ht4 Agonists

Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Animal research suggests that L-lysine is a partial serotonin receptor 4 (5-HT4) antagonist and inhibits diarrhea induced by the 5-HT4 agonist, 5-hydroxytryptophane.

Likelihood Unlikely Evidence D
L-Lysine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Hair Multivitamin, from the product label.

California Gold Nutrition

See all California Gold Nutrition products
Name
Madre Labs, LLC
Street Address
17400 Laguna Canyon Rd. Suite 400
City
Irvine
State
CA
ZipCode
92618
Web Address
www.calgn.com
Pharmacist Counseling Corner

Hair Multivitamin by California Gold Nutrition: Common Questions

Does Hair Multivitamin by California Gold Nutrition interact with any medications?
Yes. Based on its ingredients, Hair Multivitamin has a known interaction with 732 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Hair Multivitamin contains 15 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.
Can I take this if I'm pregnant?
Most ingredients are likely safe or possibly safe at standard prenatal doses—folic acid is actually recommended during pregnancy to prevent birth defects. However, some ingredients lack sufficient pregnancy safety data (L-lysine, hydrolyzed collagen, hyaluronic acid), and evening primrose oil is best avoided in pregnancy unless your doctor advises otherwise. Talk with your doctor or pharmacist before starting to ensure all ingredients are appropriate for you.
Can I take this while breastfeeding?
Most ingredients are likely safe at recommended amounts while breastfeeding, though a few (L-lysine, hyaluronic acid, hydrolyzed collagen) have limited safety data. Check with your doctor or pharmacist to confirm the dose is appropriate for your situation.
What is biotin, and does it actually help hair?
Biotin is a B vitamin that's involved in metabolism and hair structure. In our data, biotin shows possibly ineffective or insufficient evidence for hair loss (alopecia areata). The evidence for biotin supporting hair growth specifically is not established in the information we hold.
Will this product cause side effects?
Most ingredients are generally well tolerated at the doses in a standard multivitamin. The most common mild side effects from individual ingredients include GI upset (nausea, diarrhea, stomach cramps) and, with zinc, a metallic taste. High doses of vitamin B6 over time can cause nerve damage, but standard supplement amounts are generally safe. If you have any concerns, talk with your pharmacist about the dose in this specific product.
Is there any ingredient in here that interacts with a lot of medications?
Yes—zinc and vitamin C each interact with multiple medication types, and evening primrose oil has several documented interactions. Additionally, folic acid has interactions with seizure medications and cancer drugs, and vitamin B6 interacts with blood pressure and seizure medications. Use the medication checker on this page to search your exact drugs before starting.
Can I take this with my birth control?
Possibly, but check first. Vitamin C in this product may increase estrogen levels in oral contraceptives, which could affect their effectiveness or side effect profile. Talk with your doctor or pharmacist to see if a dose adjustment is needed or if spacing doses helps.

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.

Hair Multivitamin label
Go deeper

The Full Monographs Behind Hair Multivitamin’s Ingredients

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

Herb & supplement monograph

Vitamin B6

Interacts with 210 drugs

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is best known for helping with pregnancy-rel...

Read the full Vitamin B6 monograph → Herb & supplement monograph

Biotin

Biotin (vitamin B7) is a water-soluble vitamin your body needs to turn food into energy and to support healthy hair, skin, and nails. Most people get plenty from a normal diet, and true defi...

Read the full Biotin monograph → Herb & supplement monograph

Methionine

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a normal diet, and supplements are generally no...

Read the full Methionine monograph → 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

Thiamine

Interacts with 3 drugs

Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get enough from food, but supplements are clear...

Read the full Thiamine monograph → Herb & supplement monograph

Folic Acid

Interacts with 40 drugs

Folic acid is the man-made form of vitamin B9 and is one of the most well-studied supplements, especially for preventing serious birth defects when taken before and during early pregnancy. I...

Read the full Folic Acid monograph → Herb & supplement monograph

L-cysteine

Interacts with 86 drugs

L-cysteine is a sulfur-containing amino acid your body uses to make proteins and the antioxidant glutathione. Most people get enough from food, and supplements are usually well tolerated, bu...

Read the full L-cysteine monograph → Herb & supplement monograph

Copper

Interacts with 31 drugs

Copper is an essential trace mineral your body needs in small amounts for making red blood cells, supporting nerves and bones, and helping enzymes work. Most people get enough copper from fo...

Read the full Copper 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

Pantothenic Acid

Pantothenic acid is vitamin B5, an essential nutrient your body uses to turn food into energy. True deficiency is very rare because it is found in nearly all foods, and most people meet thei...

Read the full Pantothenic Acid monograph → Herb & supplement monograph

Lysine

Interacts with 1 drug

Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to try to prevent or shorten cold sores, but...

Read the full Lysine monograph → Herb & supplement monograph

Riboflavin

Interacts with 20 drugs

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally very safe at typical doses, and the stro...

Read the full Riboflavin monograph → Herb & supplement monograph

Hyaluronic Acid

Hyaluronic acid is a natural substance in the body that helps hold water in the skin, joints, and eyes. Oral and topical products are popular for skin moisture and joint comfort, and the evi...

Read the full Hyaluronic Acid monograph → Herb & supplement monograph

Collagen Peptides

Collagen peptides are a well-absorbed form of protein that may modestly improve skin elasticity and joint comfort for some people, though evidence is still developing and results vary. They...

Read the full Collagen Peptides monograph → Herb & supplement monograph

Evening Primrose

Interacts with 234 drugs

Evening primrose oil is a seed oil rich in gamma-linolenic acid (GLA), an omega-6 fatty acid, that is popularly used for skin conditions, PMS, and breast pain. The evidence behind most of th...

Read the full Evening Primrose monograph →
Sources

Sources & How We Checked

Hair Multivitamin'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 325 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 B6 32 references
  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  2. 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
  3. Geerling BJ, Dagnelie PC, Badart-Smook A, et al. Diet as a risk factor for the development of ulcerative colitis. Am J Gastroenterol 2000;95:1008-13. PubMed
  4. South M. Neonatal seizures after pyridoxine use -- reply. Lancet 1999;354:2083. PubMed
  5. 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
  6. Baxter P, Aicardi J. Neonatal seizures after pyridoxine use. Lancet 1999;354:2082-3. PubMed
  7. Bendich A, Cohen M. Vitamin B6 safety issues. Ann N Y Acad Sci 1990;585:321-30.
  8. Schaumburg H, Kaplan J, Windebank A. Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. N Engl J Med 1983;309:445-8. PubMed
  9. Gordon N. Pyridoxine dependency: an update. Dev Med Child Neurol 1997;39:63-5. PubMed
  10. Lewis PJ. Pain in the hand and wrist. Pyridoxine supplements may help patients with carpal tunnel syndrome. BMJ 1995;310:1534. PubMed
  11. Kaufman G. Pyridoxine against amiodarone-induced photosensitivity (letter). Lancet 1984;1:51-2. PubMed
  12. Mulrow JP, Mulrow CD, McKenna WJ. Pyridoxine and amiodarone-induced photosensitivity. Ann Intern Med 1985;103:68-9. PubMed
  13. Kawada A, Kashima A, Shiraishi H, et al. Pyridoxine-induced photosensitivity and hypophosphatasia. Dermatology 2000;201:356-60.. PubMed
  14. Vasile A, Goldberg R, Kornberg B. Pyridoxine toxicity: report of a case. J Am Osteopath Assoc 1984;83:790-1. DOI
  15. Hansson O, Sillanpaa M. Pyridoxine and serum concentration of phenytoin and phenobarbitone. Lancet 1976;1:256. DOI
  16. Jansen T, Romiti R, Kreuter A, Altmeyer P. Rosacea fulminans triggered by high-dose vitamins B6 and B12. J Eur Acad Dermatol Venereol 2001;15:484-5..
  17. Chittumma P, Kaewkiattikun K, Wiriyasiriwach B. Comparison of the effectiveness of ginger and vitamin B6 for treatment of nausea and vomiting in early pregnancy: a randomized double-blind controlled trial. J Med Assoc Thai 2007;90:15-20.
  18. Hatzitolios, A., Iliadis, F., Katsiki, N., and Baltatzi, M. Is the anti-hypertensive effect of dietary supplements via aldehydes reduction evidence based? A systematic review. Clin Exp.Hypertens. 2008;30(7):628-639. PubMed
  19. Vasdev, S., Ford, C. A., Parai, S., Longerich, L., and Gadag, V. Dietary vitamin B6 supplementation attenuates hypertension in spontaneously hypertensive rats. Mol.Cell Biochem. 1999;200(1-2):155-162.
  20. de, Vogel S., Dindore, V., van, Engeland M., Goldbohm, R. A., van den Brandt, P. A., and Weijenberg, M. P. Dietary folate, methionine, riboflavin, and vitamin B-6 and risk of sporadic colorectal cancer. J Nutr 2008;138(12):2372-2378. PubMed
  21. Hagen, I., Nesheim, B. I., and Tuntland, T. No effect of vitamin B-6 against premenstrual tension. A controlled clinical study. Acta Obstet.Gynecol.Scand. 1985;64(8):667-670. PubMed
  22. Aybak, M., Sermet, A., Ayyildiz, M. O., and Karakilcik, A. Z. Effect of oral pyridoxine hydrochloride supplementation on arterial blood pressure in patients with essential hypertension. Arzneimittelforschung. 1995;45(12):1271-1273.
  23. Lal, K. J., Dakshinamurti, K., and Thliveris, J. The effect of vitamin B6 on the systolic blood pressure of rats in various animal models of hypertension. J Hypertens. 1996;14(3):355-363. PubMed
  24. Lauritzen CH, Reuter HD, Repges R, Bohnert K, and Schmidt U. Treatment of premenstrual tension syndrome with Vitex agnus castus. Controlled, double-blind study versus pyridoxine. Phytomed 1997;4(3):183-189. PubMed
  25. Fonseca VA, Lavery LA, Thethi TK, et al. Metanx in type 2 diabetes with peripheral neuropathy: A randomized trial. Am J Med 2013;126(2):141-9. PubMed
  26. Hankey GJ, Eikelboom JW, Yi Q, et al. Treatment with B vitamins and incidence of cancer in patients with previous stroke or transient ischemic attack: Results of a randomized placebo-controlled trial. Stroke 2012;43(6):1572-7. PubMed
  27. Hoyer-Kuhn H, Kohbrok S, Volland R, Franklin J, Hero B, Beck BB, Hoppe B. Vitamin B6 in primary hyperoxaluria I: first prospective trial after 40 years of practice. Clin J Am Soc Nephrol. 2014 Mar;9(3):468-77. PubMed
  28. Mahmoud A, Tabassum S, Al Enazi S, et al. Amelioration of levetiracetam-induced behavioral side effects by pyridoxine. A randomized double blind controlled study. Pediatr Neurol 2021;119:15-21. PubMed
  29. Gupta M, Gallante B, Bamberger JN, et al. Prospective randomized evaluation of idiopathic hyperoxaluria treatments. J Endourol 2021;35(12):1844-1851. PubMed
  30. Li H, Chen M, Liang S, et al. Excessive vitamin B6 during treatment is related to poor prognosis of patients with nasopharyngeal carcinoma: A U-shaped distribution suggests low dose supplement. Clin Nutr 2021;40(4):2293-2300. PubMed
  31. Tanigawa J, Nabatame S, Tominaga K, et al. High-dose pyridoxine treatment for inherited glycosylphosphatidylinositol deficiency. Brain Dev 2021;43(6):680-687. PubMed
  32. Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin No. 189: Nausea And Vomiting Of Pregnancy. Obstet Gynecol. 2018;131(1):e15-e30. PubMed

See these in context on the Vitamin B6 monograph →

Folic Acid 56 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Duhra P. Treatment of gastrointestinal symptoms associated with methotrexate therapy for psoriasis. J Am Acad Dermatol 1993;28:466-9. PubMed
  3. Morgan SL, Baggott JE, Vaughn WH, et al. Supplementation with folic acid during methotrexate therapy for rheumatoid arthritis. A double-blind, placebo-controlled trial. Ann Intern Med 1994;121:833-41. PubMed
  4. Froscher W, Maier V, Laage M, et al. Folate deficiency, anticonvulsant drugs, and psychiatric morbidity. Clin Neuropharmacol 1995;18:165-82. PubMed
  5. Lewis DP, Van Dyke DC, Willhite LA, et al. Phenytoin-folic acid interaction. Ann Pharmacother 1995;29:726-35. PubMed
  6. Berg MJ, Stumbo PJ, Chenard CA, et al. Folic acid improves phenytoin pharmacokinetics. J Am Diet Assoc 1995;95:352-6. PubMed
  7. Berg MJ, Fincham RW, Ebert BE, et al. Phenytoin pharmacokinetics: Before and after folic acid administration. Epilepsia 1992;33:712-20. PubMed
  8. Shafer RB, Nuttall FQ. Calcium and folic acid absorption in patients taking anticonvulsant drugs. J Clin Endocrinol Metab 1975;41:1125-9. PubMed
  9. Leeb BF, Witzmann G, Ogris E, et al. Folic acid and cyanocobalamin levels in serum and erythrocytes during low-dose methotrexate therapy of rheumatoid arthritis and psoriatic arthritis patients. Clin Exp Rheumatol 1995;13:459-63.
  10. Morgan SL, Baggott JE, Lee JY, Alarcón GS. Folic acid supplementation prevents deficient blood folate levels and hyperhomocysteinemia during longterm, low dose methotrexate therapy for rheumatoid arthritis: implications for cardiovascular disease preventi
  11. Dijkmans BA. Folate supplementation and methotrexate. Br J Rheumatol 1995;34:1172-4. PubMed
  12. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  13. Lambie DG, Johnson RH. Drugs and folate metabolism. Drugs 1985;30:145-55. PubMed
  14. Amer College of Rheumatology ad hoc committee on clinical guidelines. Guidelines for monitoring drug therapy in rheumatoid arthritis. Arthritis Rheum 1996;39:723-31. DOI
  15. Suitor CW, Bailey LB. Dietary folate equivalents: interpretation and application. J Am Diet Assoc 2000;100:88-94. PubMed
  16. 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
  17. Sandoval M, Charbonnet RM, Okuhama NN, et al. Cat's claw inhibits TNFalpha production and scavenges free radicals: role in cytoprotection. Free Radic Biol Med 2000;29:71-78.
  18. Antony AC. Megaloblastic Anemias. In: Hoffman R, Benz Jr EJ, Shattil SJ, et al. Hematology: Basic Principles and Practice. 3rd ed. New York, NY: Churchill Livingstone 2000: 451-79.
  19. Reynolds EH. Neurological aspects of folate and vitamin B12 metabolism. Clin Haematol 1976;5:661-96. DOI
  20. Reynolds EH. Folate metabolism and anticonvulsant therapy. Proc R Soc Med 1974;67:68.
  21. Ortiz Z, Shea B, Suarez Almazor M, et al. Folic acid and folinic acid for reducing side effects in patients receiving methotrexate for rheumatoid arthritis (Cochrane Review). Cochrane Database Syst Rev 2000;2:CD000951. PubMed
  22. Van Delden C, Hirschel B. Folinic acid supplements to pyrimethamine-sulfadiazine for Toxoplasma encephalitis are associated with better outcome (letter). J Infect Dis 1996;173:1294-5. PubMed
  23. Schroder H, Clausen N, Ostergard E, Pressler T. Folic acid supplements in vitamin tablets: a determinant of hematological drug tolerance in maintenance therapy of childhood acute lymphoblastic leukemia. Ped Hematol Oncol 1986;3:241-7. PubMed
  24. Lange H, Suryapranata H, De Luca G, et al. Folate therapy and in-stent restenosis after coronary stenting. N Engl J Med 2004;350:2673-81. PubMed
  25. Morris MC, Evans DA, Bienias JL, et al. Dietary folate and vitamin B12 intake and cognitive decline among community-dwelling older persons. Arch Neurol 2005;62:641-5. PubMed
  26. Bonaa KH, Njolstad I, Ueland PM, et al. NORVIT: Homocysteine lowering and cardiovascular events after acute myocardial infarction. N Enlg J Med 2006;354:1578-88. PubMed
  27. 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
  28. Figueiredo JC, Grau MV, Haile RW, et al. Folic acid and risk of prostate cancer: Results from a randomized clinical trial. J Natl Cancer Inst 2009;101:432-5. PubMed
  29. Clippe C, Freyer G, Milano G, Trillet-Lenoir V. Lethal toxicity of capecitabine due to abusive folic acid prescription. Clin Oncol (R Coll Radiol) 2003;15:299-300. PubMed
  30. Bedford Laboratories. Leucovorin calcium [package insert]. Bedford, OH. September 2008. Available at: http://www.bedfordlabs.com/BedfordLabsWeb/products/inserts/LCV-P02.pdf.
  31. Ebbing M, Bonaa KH, Nygard O, et al. Cancer incidence and mortality after treatment with folic acid and vitamin B12. JAMA 2009;302:2119-26.
  32. Haberg, S. E., London, S. J., Stigum, H., Nafstad, P., and Nystad, W. Folic acid supplements in pregnancy and early childhood respiratory health. Arch Dis.Child 2009;94(3):180-184. PubMed
  33. Whitrow, M. J., Moore, V. M., Rumbold, A. R., and Davies, M. J. Effect of supplemental folic acid in pregnancy on childhood asthma: a prospective birth cohort study. Am J Epidemiol. 12-15-2009;170(12):1486-1493. PubMed
  34. Collin, S. M., Metcalfe, C., Refsum, H., Lewis, S. J., Zuccolo, L., Smith, G. D., Chen, L., Harris, R., Davis, M., Marsden, G., Johnston, C., Lane, J. A., Ebbing, M., Bonaa, K. H., Nygard, O., Ueland, P. M., Grau, M. V., Baron, J. A., Donovan, J. L., Nea
  35. Baggott, J. E., Oster, R. A., and Tamura, T. Meta-analysis of cancer risk in folic acid supplementation trials. Cancer Epidemiol. 2012;36(1):78-81. PubMed
  36. Fonseca VA, Lavery LA, Thethi TK, et al. Metanx in type 2 diabetes with peripheral neuropathy: A randomized trial. Am J Med 2013;126(2):141-9. PubMed
  37. Hankey GJ, Eikelboom JW, Yi Q, et al. Treatment with B vitamins and incidence of cancer in patients with previous stroke or transient ischemic attack: Results of a randomized placebo-controlled trial. Stroke 2012;43(6):1572-7. PubMed
  38. Taneja S, Strand TA, Kumar T, et al. Folic acid and vitamin B-12 supplementation and common infections in 6-30-mo-old children in India: a randomized placebo-controlled trial. Am J Clin Nutr 2013;98(3):731-7. PubMed
  39. van Wijngaarden JP, Swart KM, Enneman AW, et al. Effect of daily vitamin B-12 and folic acid supplementation on fracture incidence in elderly individuals with an elevated plasma homocysteine concentration: B-PROOF, a randomized controlled trial. Am J Clin
  40. Qin X, Fan F, Cui Y, Chen F, Chen Y, Cheng X, Li Y, Wang B, Xu X, Xu X, Huo Y, Wang X. Folic acid supplementation with and without vitamin B6 and revascularization risk: a meta-analysis of randomized controlled trials. Clin Nutr. 2014;33(4):603-12. PubMed
  41. Crider KS, Cordero AM, Qi YP, Mulinare J, Dowling NF, Berry RJ. Prenatal folic acid and risk of asthma in children: a systematic review and meta-analysis. Am J Clin Nutr. 2013;98(5):1272-81. PubMed
  42. Matsubara S, Imai K, Murayama K, Higashizawa T. Severe liver dysfunction during nausea and vomiting of pregnancy: folic acid supplement as a suggested culprit. J Obstet Gynaecol. 2012;32(7):701-2. PubMed
  43. Qin X, Cui Y, Shen L, Sun N, Zhang Y, Li J, Xu X, Wang B, Xu X, Huo Y, Wang X. Folic acid supplementation and cancer risk: a meta-analysis of randomized controlled trials. Int J Cancer. 2013 1;133(5):1033-41. PubMed
  44. Tio M, Andrici J, Cox MR, Eslick GD. Folate intake and the risk of prostate cancer: a systematic review and meta-analysis. Prostate Cancer Prostatic Dis. 2014;17(3):213-9. PubMed
  45. Tomaszewski JJ, Richman EL, Sadetsky N, O'Keefe DS, Carroll PR, Davies BJ, Chan JM. Impact of folate intake on prostate cancer recurrence following definitive therapy: data from CaPSURE. J Urol. 2014;191(4):971-6. PubMed
  46. Valera-Gran D, García de la Hera M, Navarrete-Muñoz EM, Fernandez-Somoano A, Tardón A, Julvez J, Forns J, Lertxundi N, Ibarluzea JM, Murcia M, Rebagliato M, Vioque J; Infancia y Medio Ambiente (INMA) Project. Folic acid supplements during pregnancy and ch
  47. Van Der Woude DA, De Vries J, Van Wijk EM, Verzijl JM, Pijnenborg JM. A randomized controlled trial examining the addition of folic acid to iron supplementation in the treatment of postpartum anemia. Int J Gynaecol Obstet. 2014;126(2):101-5. PubMed
  48. Vila-Nova C, Wehby GL, Queirós FC, Chakraborty H, Félix TM, Goco N, Moore J, Gewehr EV, Lins L, Affonso CM, Murray JC. Periconceptional use of folic acid and risk of miscarriage - findings of the Oral Cleft Prevention Program in Brazil. J Perinat Med. 201 PubMed
  49. Vollset SE, Clarke R, Lewington S, Ebbing M, Halsey J, Lonn E, Armitage J, Manson JE, Hankey GJ, Spence JD, Galan P, Bønaa KH, Jamison R, Gaziano JM, Guarino P, Baron JA, Logan RF, Giovannucci EL, den Heijer M, Ueland PM, Bennett D, Collins R, Peto R; B-V
  50. Wehby GL, Félix TM, Goco N, Richieri-Costa A, Chakraborty H, Souza J, Pereira R, Padovani C, Moretti-Ferreira D, Murray JC. High dosage folic acid supplementation, oral cleft recurrence and fetal growth. Int J Environ Res Public Health. 2013 4;10(2):590-6 PubMed
  51. Fanidi A, Carreras-Torres R, Larose TL, et al. Is high vitamin B12 status a cause of lung cancer? Int J Cancer. 2019 Sep 15;145(6):1499-1503. PubMed
  52. Liu J, Li Z, Ye R, Liu J, Ren A. Periconceptional folic acid supplementation and risk of parent-reported asthma in children at 4-6 years of age. ERJ Open Res. 2020;6(1):00250-2019. PubMed
  53. Houghton LA, Sherwood KL, Pawlosky R, Ito S, O'Connor DL. [6S]-5-Methyltetrahydrofolate is at least as effective as folic acid in preventing a decline in blood folate concentrations during lactation. Am J Clin Nutr. 2006 Apr;83(4):842-50. PubMed
  54. Houghton LA, Yang J, O'Connor DL. Unmetabolized folic acid and total folate concentrations in breast milk are unaffected by low-dose folate supplements. Am J Clin Nutr. 2009 Jan;89(1):216-20. PubMed
  55. Chan SL, Chan AWH, Mo F, et al. Association Between Serum Folate Level and Toxicity of Capecitabine During Treatment for Colorectal Cancer. Oncologist. 2018 Dec;23(12):1436-1445. PubMed
  56. Sarris J, Ravindran A, Yatham LN, et al. Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety T

See these in context on the Folic Acid monograph →

Biotin 4 references
  1. Debourdeau PM, Djezzar S, Estival JL, et al. Life-threatening eosinophilic pleuropericardial effusion related to vitamins B5 and H. Ann Pharmacother 2001;35:424-6. DOI
  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. Mock DM, Quirk JG, Mock NI. Marginal biotin deficiency during normal pregnancy. Am J Clin Nutr 2002;75:295-9. PubMed
  4. Sedel F, Papeix C, Bellanger A, Touitou V, Lebrun-Frenay C, Galanaud D, et al. High doses of biotin in chronic progressive multiple sclerosis: a pilot study.Mult Scler Relat Disord. 2015;4(2):159-69. doi: 10.1016/j.msard.2015.01.005. PubMed

See these in context on the Biotin monograph →

Methionine 12 references
  1. La Vecchia C, Negri E, Franceschi S, Decarli A. Case-control study on influence of methionine, nitrite, and salt on gastric carcinogenesis in northern Italy. Nutr Cancer 1997;27:65-8. PubMed
  2. Btaiche IF, Khalidi N. Parenteral nutrition-associated liver complications in children. Pharmacotherapy 2002;22:188-211.. PubMed
  3. Cottington EM, LaMantia C, Stabler SP, et al. Adverse event associated with methionine loading test: a case report. Arterioscler Thromb Vasc Biol 2002;22:1046-50.. PubMed
  4. Anon. Should methionine be added to paracetamol formulations? Drug Ther Perspect 1997;10:11-3. DOI
  5. Smulders, Y. M., Rakic, M., Slaats, E. H., Treskes, M., Sijbrands, E. J., Odekerken, D. A., Stehouwer, C. D., and Silberbusch, J. Fasting and post-methionine homocysteine levels in NIDDM. Determinants and correlations with retinopathy, albuminuria, and c
  6. McAuley, D. F., Hanratty, C. G., McGurk, C., Nugent, A. G., and Johnston, G. D. Effect of methionine supplementation on endothelial function, plasma homocysteine, and lipid peroxidation. J.Toxicol.Clin.Toxicol. 1999;37(4):435-440. PubMed
  7. Hanratty, C. G., McGrath, L. T., McAuley, D. F., Young, I. S., and Johnston, G. D. The effects of oral methionine and homocysteine on endothelial function. Heart 2001;85(3):326-330. PubMed
  8. Ward, M., McNulty, H., McPartlin, J., Strain, J. J., Weir, D. G., and Scott, J. M. Effect of supplemental methionine on plasma homocysteine concentrations in healthy men: a preliminary study. Int.J.Vitam.Nutr.Res. 2001;71(1):82-86. PubMed
  9. Yaghmai, R., Kashani, A. H., Geraghty, M. T., Okoh, J., Pomper, M., Tangerman, A., Wagner, C., Stabler, S. P., Allen, R. H., Mudd, S. H., and Braverman, N. Progressive cerebral edema associated with high methionine levels and betaine therapy in a patient
  10. Talukdar R, Murthy HV, Reddy DN. Role of methionine containing antioxidant combination in the management of pain in chronic pancreatitis: a systematic review and meta-analysis. Pancreatology 2015;15(2):136-44. PubMed
  11. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: The National Academies Press, 2005. Available at: https://doi.org/10.17226 DOI
  12. Khairan P, Sobue T, Eshak ES, et al. Association of B Vitamins and Methionine Intake with the Risk of Gastric Cancer: The Japan Public Health Center-based Prospective Study. Cancer Prev Res (Phila) 2022;15(2):101-110. PubMed

See these in context on the Methionine monograph →

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 →

Thiamine 7 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. 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
  3. 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
  4. Rogovik, A. L., Vohra, S., and Goldman, R. D. Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? Ann.Pharmacother. 2010;44(2):311-324. PubMed
  5. Arruti N, Bernedo N, Audicana MT, Villarreal O, Uriel O, Muñoz D. Systemic allergic dermatitis caused by thiamine after iontophoresis. Contact Dermatitis. 2013 Dec;69(6):375-6. PubMed
  6. Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
  7. Vora B, Wen A, Yee SW, et al. The Effect of Trimethoprim on Thiamine Absorption: A Transporter-Mediated Drug-Nutrient Interaction. Clin Pharmacol Ther 2023;114(2):381-392.

See these in context on the Thiamine monograph →

L-cysteine 2 references
  1. Dowlati Y, Maheux M, Meyer JH. The effect of oral L-cysteine on breast milk and plasma cysteine concentrations. Neuropsychiatr Dis Treat 2020;16:3163-3172.
  2. Lee S, Han KH, Nakamura Y, et al. Dietary L-cysteine improves the antioxidative potential and lipid metabolism in rats fed a normal diet. Biosci Biotechnol Biochem 2013;77(7):1430-4.

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Copper 11 references
  1. Murry JJ, Healy MD. Drug-mineral interactions: a new responsibility for the hospital dietician. J Am Diet Assoc 1991;91:66-73.
  2. Campbell IA, Elmes PC. Ethambutol and the eye: zinc and copper (letter). Lancet 1975;2:711. DOI
  3. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  4. Kozak SF, Inderlied CB, Hsu HY, et al. The role of copper on ethambutol's antimicrobial action and implications for ethambutol-induced optic neuropathy. Diag Microbiol Infect Dis 1998;30:83-7. PubMed
  5. 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.
  6. Cantilena LR, Klaassen CD. The effect of chelating agents on the excretion of endogenous metals. Toxicol Appl Pharmacol 1982;63:344-50.
  7. Babic Z, Tariba B, Kovacic J, Pizent A, Varnai VM, Macan J. Relevance of serum copper elevation induced by oral contraceptives: a meta-analysis. Contraception. 2013 Jun;87(6):790-800. PubMed
  8. Qui Q, Zhang F, Zhu W, Wu J, Liang M. Copper in diabetes mellitus: a meta-analysis and systematic review of plasma and serum studies. Biol Trace Elem Res 2017;177(1):53-63.
  9. Walker-Smith PK, Keith DJ, Kennedy CT, Sansom JE. Allergic contact dermatitis caused by copper. Contact Dermatitis 2016;75(3):186-7. PubMed
  10. Gallentine A. Third-degree burn on the neuropathic lower extremity in a patient with diabetes while wearing a copper-containing compression sock: a case report. Wound Manag Prev 2021;67(12):26-29. DOI
  11. Chung KJ, Chin YM, Wong MS, Sanmugam A, Singaravel S, Nah SA. Effectiveness of table salt versus copper sulphate in treating umbilical granuloma: A pilot randomized controlled trial. J Pediatr Surg 2022;57(2):261-265. PubMed

See these in context on the Copper 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 →

Pantothenic Acid 11 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. 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
  3. Debourdeau PM, Djezzar S, Estival JL, et al. Life-threatening eosinophilic pleuropericardial effusion related to vitamins B5 and H. Ann Pharmacother 2001;35:424-6. DOI
  4. Schmuth, M., Wimmer, M. A., Hofer, S., Sztankay, A., Weinlich, G., Linder, D. M., Elias, P. M., Fritsch, P. O., and Fritsch, E. Topical corticosteroid therapy for acute radiation dermatitis: a prospective, randomized, double-blind study. Br.J.Dermatol. 2 PubMed
  5. Schreck, U., Paulsen, F., Bamberg, M., and Budach, W. Intraindividual comparison of two different skin care conceptions in patients undergoing radiotherapy of the head-and-neck region. Creme or powder? Strahlenther.Onkol. 2002;178(6):321-329. PubMed
  6. Herbst, R. A., Uter, W., Pirker, C., Geier, J., and Frosch, P. J. Allergic and non-allergic periorbital dermatitis: patch test results of the Information Network of the Departments of Dermatology during a 5-year period. Contact Dermatitis 2004;51(1):13-1 PubMed
  7. Champault, G. and Patel, J. C. [Treatment of constipation with Bepanthene]. Med.Chir Dig. 1977;6(1):57-59.
  8. Scott LN, Fiume M, Bergfeld WF, et al. Safety Assessment of Panthenol, Pantothenic Acid, and Derivatives as Used in Cosmetics. Int J Toxicol 2022;41(3_suppl):77-128. PubMed
  9. Han J, Warshaw EM. Allergic Contact Dermatitis to Panthenol in "Hypoallergenic" Products. Dermatitis 2023;34(1):62-63. PubMed
  10. Blanchard G, Kerre S, Walker A, et al. Allergic contact dermatitis from pantolactone and dexpanthenol in wound healing creams. Contact Dermatitis 2022;87(5):468-471. PubMed
  11. Peltier E, Trapp S, de Salvo R, et al. A new dexpanthenol-containing liquid cleanser for atopic-prone skin: Results from two prospective clinical studies evaluating cutaneous tolerability, moisturization potential, and effects on barrier function. J Cosme PubMed

See these in context on the Pantothenic Acid monograph →

Lysine 7 references
  1. Thein DJ, Hurt WC. Lysine as a prophylactic agent in the treatment of recurrent herpes simplex labialis. Oral Surg Oral Med Oral Pathol 1984;58:659-66. PubMed
  2. McCune MA, Perry HO, Muller SA, O'Fallon WM. Treatment of recurrent herpes simplex infections with L-lysine monohydrochloride. Cutis 1984;34:366-73.
  3. DiGiovanna JJ, Blank H. Failure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Arch Dermatol 1984;120:48-51. DOI
  4. Milman N, Scheibel J, Jessen O. Lysine prophylaxis in recurrent herpes simplex labialis: a double-blind, controlled crossover study. Acta Derm Venereol 1980;60:85-7.
  5. Griffith RS, Walsh DE, Myrmel KH, et al. Success of L-lysine therapy in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Dermatologica 1987;175:183-90. DOI
  6. Lo JC, Chertow GM, Rennke H, Seifter JL. Fanconi's syndrome and tubulointerstitial nephritis in association with L-lysine ingestion. Am J Kidney Dis 1996;28:614-7. PubMed
  7. Smriga M, Torii K. L-Lysine acts like a partial serotonin receptor 4 antagonist and inhibits serotonin-mediated intestinal pathologies and anxiety in rats. Proc Natl Acad Sci U S A. 2003 Dec 23;100(26):15370-5.

See these in context on the Lysine monograph →

Riboflavin 5 references
  1. Schoenen J, Jacquy J, Lenaerts M. Effectiveness of high-dose riboflavin in migraine prophylaxis. A randomized controlled trial. Neurology 1998;50:466-70. PubMed
  2. 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
  3. Leeson LJ, Weidenheimer JF. Stability of tetracycline and riboflavin. J Pharm Sci. 1969;58(3):355-7. PubMed
  4. MacLennan, S. C., Wade, F. M., Forrest, K. M., Ratanayake, P. D., Fagan, E., and Antony, J. High-dose riboflavin for migraine prophylaxis in children: a double-blind, randomized, placebo-controlled trial. J Child Neurol. 2008;23(11):1300-1304.
  5. Dietary reference intakes (DRIs): estimated average requirements. Food and Nutrition Board, Institute of Medicine, National Academics. https://www.nal.usda.gov/sites/default/files/fnic_uploads//recommended_intakes_individuals.pdf Accessed July 24, 2017.

See these in context on the Riboflavin monograph →

Hyaluronic Acid 4 references
  1. Park Y, Song JS, Choi CY, Yoon KC, Lee HK, Kim HS. A randomized multicenter study comparing 0.1%, 0.15%, and 0.3% sodium hyaluronate with 0.05% cyclosporine in the treatment of dry eye. J Ocul Pharmacol Ther. 2017;33(2):66-72. PubMed
  2. U.S. Food and Drug Administration. Do Not Use Needle-Free Devices for Injection of Dermal Fillers - FDA Safety Communication. October 8, 2021. Available at: https://www.fda.gov/medical-devices/safety-communications/do-not-use-needle-free-devices-injection
  3. Disphanurat W, Srisantithum B. Efficacy and safety of 0.15% isobutylamido thiazolyl resorcinol combined with hyaluronic acid vs 0.15% isobutylamido thiazolyl resorcinol or hyaluronic acid alone in melasma treatment: A randomized evaluator-blind trial. J C PubMed
  4. Humbert P, Mikosinki J, Benchikhi H, Allaert FA. Efficacy and safety of a gauze pad containing hyaluronic acid in treatment of leg ulcers of venous or mixed origin: a double-blind, randomised, controlled trial. Int Wound J 2013;10(2):159-66. PubMed

See these in context on the Hyaluronic Acid monograph →

Collagen Peptides 2 references
  1. Trc T, Bohmová J. Efficacy and tolerance of enzymatic hydrolysed collagen (EHC) vs. glucosamine sulphate (GS) in the treatment of knee osteoarthritis (KOA). Int Orthop. 2011;35(3):341-8. PubMed
  2. Evans M, Lewis ED, Zakaria N, Pelipyagina T, Guthrie N. A randomized, triple-blind, placebo-controlled, parallel study to evaluate the efficacy of a freshwater marine collagen on skin wrinkles and elasticity. J Cosmet Dermatol. 2021;20(3):825-834. PubMed

See these in context on the Collagen Peptides monograph →

Evening Primrose 33 references
  1. Shaw D, Leon C, Kolev S, Murray V. Traditional remedies and food supplements: a 5-year toxicological study (1991-1995). Drug Saf 1997;17:342-56.
  2. Laivuori H, Hovatta O, Viinikka L, et al. Dietary supplementation with primrose oil or fish oil does not change urinary excretion of prostacyclin and thromboxane metabolites in pre-eclamptic women. Prostaglandins Leukot Essent Fatty Acids 1993;49:691-4. PubMed
  3. Dove D, Johnson P. Oral evening primrose oil: its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women (abstract). J Nurse Midwifery 1999;44:320-4. PubMed
  4. 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
  5. Cant A, Shay J, Horrobin DF. The effect of maternal supplementation with linoleic and gamma- linolenic acids on the fat composition and content of human milk: a placebo-controlled trial. J Nutr Sci Vitaminol (Tokyo) 1991;37:573-9. PubMed
  6. Keen H, Payan J, Allawi J, et al. Treatment of diabetic neuropathy with gamma-linolenic acid. The gamma-Linolenic Acid Multicenter Trial Group. Diabetes Care 1993;16:8-15.
  7. Blommers J, de Lange-De Klerk ES, Kuik DJ, et al. Evening primrose oil and fish oil for severe chronic mastalgia: a randomized, double-blind, controlled trial. Am J Obstet Gynecol 2002;187:1389-94.. DOI
  8. Cheung KL. Management of cyclical mastalgia in oriental women: pioneer experience of using gamolenic acid (Efamast) in Asia. Aust N Z J Surg 1999;69:492-4..
  9. Das UN. The lipids that matter from infant nutrition to insulin resistance. Prostaglandins Leukot Essent Fatty Acids 2002;67:1-12. PubMed
  10. Wedig KE, Whitsett JA. Down the primrose path: petechiae in a neonate exposed to herbal remedy for parturition. J Pediatr 2008;152:140, 140.e1. PubMed
  11. Ty-Torredes KA. The effect of oral evening primrose oil on bishop score and cervical length amongst term gravidas. Am J Obstet Gynecol. 2006;195(6 Suppl 1):S30.
  12. Moodley J and Norman RJ. Attempts at dietary alteration of prostaglandin pathways in the management of pre-eclampsia. Prostaglandins Leukot Essent Fatty Acids 1989;37(3):145-147. PubMed
  13. Tong M. [Treatment of hyperlipemia with evening primrose oil capsules]. Zhong Xi Yi Jie He Za Zhi. 1988;8:469-71, 452-3.
  14. Holman CP and Bell AF. A trial of evening primrose oil in the treatment of chronic schizophrenia. J Orhtomolecular Psych 1983;12:302-304.
  15. 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
  16. Zou L, Harkey MR, and Henderson GL. Effects of herbal components on cDNA-expressed cytochrome P450 enzyme catalytic activity. Life Sci 8-16-2002;71(13):1579-1589. PubMed
  17. Yoon, S., Lee, J., and Lee, S. The therapeutic effect of evening primrose oil in atopic dermatitis patients with dry scaly skin lesions is associated with the normalization of serum gamma-interferon levels. Skin Pharmacol Appl.Skin Physiol 2002;15(1):20- PubMed
  18. Bamford, J. T., Gibson, R. W., and Renier, C. M. Atopic eczema unresponsive to evening primrose oil (linoleic and gamma- linolenic acids). J Am.Acad.Dermatol. 1985;13(6):959-965.
  19. Preece PE, Hanslip JI Gilbert L. Evening primrose oil (Efamol) for mastalgia. In: Horrobin DF. Clinical Uses of Essential Fatty Acids . Montreal, Quebec: Eden;1982.
  20. Parveen, S. Sarwar G. Ali M. Channa G. A. Danazol versus oil of evening primrose in the treatment of mastalgia. Pakistan Journal of Surgery. 2007;23(1):10-13.
  21. Belch JJF, Shaw B, O'Dowd A, et al. Evening primrose oil (Efamol) as a treatment for cold-induced vasospasm (Raynaud's phenomenon). Prog Lipid Res 1986;25:335-40.
  22. Johnson, M., Ostlund, S., Fransson, G., Kadesjo, B., and Gillberg, C. Omega-3/omega-6 fatty acids for attention deficit hyperactivity disorder: a randomized placebo-controlled trial in children and adolescents. J.Atten.Disord. 2009;12(5):394-401. PubMed
  23. Farzaneh F, Fatehi S, Sohrabi MR, Alizadeh K. The effect of oral evening primrose oil on menopausal hot flashes: a randomized clinical trial. Arch Gynecol Obstet 2013;288(5):1075-9. PubMed
  24. Puri BK. The safety of evening primrose oil in epilepsy. Prostaglandins Leukotrienes Essential Fatty Acids 2007;77:101-3. PubMed
  25. 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
  26. Osman M, Badawi E. Evening primrose oil reducing serum lithium concentration. Ther Adv Psychopharmacol. 2016 Oct;6(5):343-44. PubMed
  27. Kalati M, Kashanian M, Jahdi F, Naseri M, Haghani H, SHeikhansari N. Evening primrose oil and labour, is it effective? A randomized clinical trial. J Obstet Gynaecol. 2018 Feb 9:1-5.
  28. Sharif SN, Darsareh F. Impact of evening primrose oil consumption on psychological symptoms of postmenopausal women: a randomized double-blinded placebo-controlled clinical trial. Menopause. 2020;27(2):194-198. PubMed
  29. Shahraki AD, Mirhoseini S, Movahedi M, Hajihashemy M, Haghollahi F. Comparative Study of the Effect of Vaginal use of Primrose Oil with Misoprostol on Cervical Preparation of Prim Gravid Women: A Double-blind Clinical Trial. Adv Biomed Res 2023;12:78. PubMed
  30. Shahinfar S, Abedi P, Jahanfar S, Khajehpoor M, Chashmyazdan M. The effect of evening primrose oil on cervical ripening and birth outcomes: A systematic review and meta-analysis. Heliyon 2023;9(2):e13414. PubMed
  31. Mahmoodinasab M, Loripoor M, Vazirinejad R, Aminzadeh F. Effect of misoprostol with and without evening primrose (Oenothera biennis) on induction of missed abortion. Avicenna J Phytomed 2023;13(5):454-462.
  32. Hashemi H, Hasanpoor-Azghady SB, Farahani M, Amiri-Farahani L. Comparison of the effect of vaginal misoprostol and evening primrose oil capsule with misoprostol alone on the consequences of abortion in women with intrauterine fetal death: a randomized cli
  33. Ariana S, Amjadi N, Kazemi SN, Ahmadli Z. The Use of Evening Primrose Oil for Cervical Ripening in Low-Risk Women with Term Pregnancy: A Randomized Double-Blinded Controlled Trial. Complement Med Res 2024;31(3):215-221. PubMed

See these in context on the Evening Primrose monograph →

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