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Dietary supplement

Thyroid Nutrition Ingredients & Drug Interactions

by Allergy Research Group

Thyroid Nutrition label
See full label image
Capsule Category: Botanical With Nutrients
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

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

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

The interaction bottom line Most serious interaction: Major

Thyroid Nutrition is a dietary supplement by Allergy Research Group with 8 active ingredients. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 1,488 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ashwagandha Root Extract, Coleus forskohlii Root Extract, Vitamin A. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Thyroid Nutrition by Allergy Research Group

Ask about any prescription or over-the-counter medication and we check it for interactions with Thyroid Nutrition by Allergy Research Group — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Thyroid Nutrition by Allergy Research Group

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 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 9 of its 9 active ingredients.
  • “Total Iodine/Iodide” is listed as a grouped ingredient — the label gives one combined amount (150 mcg) without saying how much of each component you get.

Thyroid Nutrition contains nine active ingredients formulated to support thyroid and metabolic function. L-Tyrosine is an amino acid and precursor to thyroid hormones; Iodine and Iodide supply this essential mineral needed for thyroid hormone synthesis; Selenium is a mineral that protects thyroid tissue and supports thyroid enzyme function; Vitamin B12 aids energy and cell metabolism; Zinc supports immune function and thyroid health; Vitamin A is a fat-soluble vitamin essential for cell growth and thyroid receptors; Ashwagandha Root Extract is an herbal adaptogen traditionally used for stress; and Coleus forskohlii Root Extract contains compounds that some research suggests may support metabolic function.

The product also contains inactive ingredients — microcrystalline cellulose, potassium hydroxide, silicon dioxide, magnesium sulfate heptahydrate, polysorbate 80, citric acid, cellulose, stearic acid, calcium stearate, and pharmaceutical glaze — which serve as binders, flow agents, and capsule materials.

Does it work?

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

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

Why this rating?
  • The label markets this product for: nutritionally support healthy thyroid function.
  • We looked for evidence on: Autoimmune thyroiditis, Hypothyroidism, Thyroid hormone synthesis, Iodine deficiency.
  • The strongest evidence on file: Iodine is rated "Likely Effective" for Iodine deficiency (Natural Medicines).
  • Also on file: Selenium is rated "Possibly Effective" for Autoimmune thyroiditis.
  • Also on file: Ashwagandha is rated "Insufficient Reliable Evidence To Rate" for Hypothyroidism.

The evidence for individual ingredients varies. L-Tyrosine is effective for phenylketonuria (PKU) and possibly effective for cognitive function and memory, but possibly ineffective for athletic performance.

Iodine is likely effective for iodine deficiency and radiation exposure, and possibly effective for oral mouth sores and gum disease. Selenium is likely effective for selenium deficiency and possibly effective for autoimmune thyroiditis and pre-eclampsia, but possibly ineffective for cholesterol problems.

Vitamin B12 is effective for B12 deficiency and possibly effective for canker sores. Zinc is effective for zinc deficiency and possibly effective for acne and age-related vision loss.

Vitamin A is effective for vitamin A deficiency and possibly effective for aging skin and measles. Ashwagandha is possibly effective for insomnia, anxiety, and stress.

Coleus forskohlii has insufficient evidence in our data for its traditional uses — angina, asthma, heart failure, and eczema are all unproven. The product as a whole is marketed for thyroid support, but the evidence for that claim specifically is not established in the data we hold.

The evidence, ingredient by ingredient Tyrosine Selenium Vitamin B12 Zinc Vitamin A Ashwagandha Coleus Iodine

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 8 of the 8 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 8 of 8.
  • General safety write-ups exist for 8 of 8.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these ingredients are generally well tolerated at recommended doses. L-Tyrosine is generally well tolerated in healthy adults but lacks long-term safety data; common side effects at higher doses include fatigue, headache, and nausea.

Iodine is safe in normal dietary amounts but high doses can cause thyroid problems, goiter, and — rarely — serious allergic reactions; some people report a metallic taste or nausea. Selenium is safe below the tolerable upper limit of 400 mcg daily but excess can cause hair loss, nail changes, and skin problems.

Vitamin B12 is very safe with no upper limit. Zinc is safe below 40 mg daily but higher doses may cause nausea, diarrhea, and metallic taste, plus long-term high doses carry a risk of copper deficiency.

Vitamin A is safe at recommended amounts but builds up in the body and high doses can cause serious liver damage, headaches, and — in pregnancy — birth defects. Ashwagandha is generally well tolerated short-term but long-term safety is unclear; rare cases of liver injury have been reported.

Coleus causes dose-related gastrointestinal upset including diarrhea in some users and may lower blood pressure.

Side effects, ingredient by ingredient Tyrosine Selenium Vitamin B12 Zinc Vitamin A Ashwagandha Coleus Iodine

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

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

Why this rating?
  • 8 of the 8 matched ingredients can interact with medications — Iodine, Vitamin B12, Ashwagandha, Vitamin A, Zinc, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium; Parkinson's medications.
  • For scale: 1,489 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 you take this, flag these with your pharmacist: thyroid hormone medications and antithyroid drugs (because tyrosine and iodine may alter effects), blood thinners and antiplatelet drugs like warfarin (selenium and coleus may increase bleeding risk), heart medications including nitrates and calcium channel blockers (coleus has Major interactions), antidiabetes drugs (ashwagandha may lower blood sugar), sedatives and benzodiazepines (ashwagandha and coleus may increase drowsiness), antibiotics including tetracyclines, quinolones, and cephalexin (zinc reduces their absorption), and HIV medications (zinc may lower levels). Also watch for metformin, lithium, and any liver-toxic medications.

Check your own medication Run your meds through the checker above

The bottom line

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

This is a multi-ingredient thyroid support formula best suited for people with confirmed thyroid nutrient gaps or underactive thyroid who've discussed it with their doctor. If you take any thyroid medications, blood thinners, heart drugs, antidiabetes medications, sedatives, or antibiotics, you'll want to check your specific medications with the tool on this page — the interaction count is high.

Avoid this product if you're pregnant (especially because of Vitamin A) or breastfeeding without medical guidance, and talk to your pharmacist or doctor before starting if you have liver disease, take multiple medications, or are on psychiatric drugs.

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

Assessment coverage: 9 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 24, 2024.

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 Thyroid Nutrition, straight from the product label.

Brand Allergy Research Group
Barcode (UPC) 713947776708
Net contents 60 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Jan 24, 2024
DSLD ID 304285
Product type Botanical With Nutrients
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 Thyroid Nutrition by Allergy Research Group, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Tablet(s)
Maximum serving Sizes:
1 Tablet(s)
Servings per container
60
UPC/BARCODE
713947776708
IngredientAmount% DV
L-Tyrosine250 mg--
Iodine60 mcg--
Selenium50 mcg91%
Vitamin B1225 mcg1042%
Zinc5 mg45%
Vitamin A150 mcg RAE17%
Ashwagandha Root Extract150 mg--
Coleus forskohlii Root Extract100 mg--
Total Iodine/Iodide150 mcg100%
Iodide90 mcg--

Other ingredients: Microcrystalline Cellulose, Potassium Hydroxide, Silicon Dioxide, Magnesium Sulfate Heptahydrate, Polysorbate 80, Citric Acid, Cellulose, Stearic Acid, Calcium Stearate, Pharmaceutical Glaze

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.
Formula

Iodine (Iodoral), selenium, zinc, and extracts of ashwagandha and Coleus forskohlii to nutritionally support healthy thyroid function. Enhanced with vegan tyrosine, and vitamins A and B12.

Thyroid Nutrition with Iodoral

Formulation

Enhanced with vegan tyrosine, and vitamins A and B12.

Hypoallergenic

Suggested/Recommended/Usage/Directions

Suggested use As a dietary supplement, 1 tablet daily with breakfast, or as directed by a health care professional.

Precautions

Warning: If pregnant or nursing, consult your healthcare practitioner before use.

Storage

Keep in a cool, dry place, tightly capped.

FDA Disclaimer Statement

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

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

Thyroid Nutrition by Allergy Research Group label

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

Thyroid Nutrition 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 Thyroid Nutrition by Allergy Research Group

These are the 8 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

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

L-Tyrosine

Interacts with
21 drugs
250 mg per serving

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performan...

L-Tyrosine monograph & interactions

Selenium

Interacts with
321 drugs
50 mcg per serving Form: Selenomethionine

Selenium is an essential trace mineral your body needs in small amounts for thyroid function, antioxidant defense, and immune health. Most people who...

Selenium monograph & interactions

Vitamin B12

Interacts with
20 drugs
25 mcg per serving Form: Methylcobalamin

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very h...

Vitamin B12 monograph & interactions

Zinc

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

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

Vitamin A

Interacts with
387 drugs
150 mcg RAE per serving Form: Retinyl Palmitate

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplemen...

Vitamin A monograph & interactions

Ashwagandha Root Extract

Interacts with
1,372 drugs
150 mg per serving Form: Withanolides

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evid...

Ashwagandha Root Extract monograph & interactions

Coleus forskohlii Root Extract

Interacts with
915 drugs
100 mg per serving Form: Forskolin

Coleus is a plant from the mint family whose root contains a compound called forskolin, often marketed for weight loss, asthma, and heart health. Whil...

Coleus forskohlii Root Extract monograph & interactions

Total Iodine/Iodide

Interacts with
7 drugs
150 mcg per serving

Iodine is an essential mineral your body needs to make thyroid hormones, and most people get enough from iodized salt, dairy, and seafood. Supplements...

Total Iodine/Iodide monograph & interactions

Other (inactive) ingredients: Microcrystalline Cellulose, Potassium Hydroxide, Silicon Dioxide, Magnesium Sulfate Heptahydrate, Polysorbate 80, Citric Acid, Cellulose, Stearic Acid, Calcium Stearate, Pharmaceutical Glaze. These complete the product’s ingredient list but are not active constituents.

Interaction report

Thyroid Nutrition by Allergy Research Group Drug Interactions

Want to check YOUR meds against Thyroid Nutrition?

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

 Go to the checker
1,488Drugs
38 Major 1,377 Moderate 73 Minor

Ingredients driving the most interactions

Ashwagandha Root Extract 1,372
Coleus forskohlii Root Extract 915
Vitamin A 387
Selenium 321
Zinc 67

Individual Drug Interactions

The ingredients in Thyroid Nutrition interact with 1,488 drugs. Click any drug to see the details.

8 of the 8 ingredients in Thyroid Nutrition interact with drugs. Each result below shows which ingredient is responsible. Ashwagandha Root Extract Coleus forskohlii Root Extract Vitamin A Selenium Zinc L-Tyrosine Vitamin B12 Total Iodine/Iodide

Each ingredient & the kinds of drugs it affects

For each ingredient in Thyroid Nutrition 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.

Ashwagandha Root Extract10 drug types · 1,372 drugs

Antidiabetes Drugs

Theoretically, taking ashwagandha with antidiabetes drugs might increase the risk of hypoglycemia.
There is preliminary clinical evidence suggesting that ashwagandha might lower blood glucose levels. Theoretically, ashwagandha might have additive effects when used with antidiabetes drugs and increase the risk of hypoglycemia.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking ashwagandha with antihypertensive drugs might increase the risk of hypotension.
Animal research suggests that ashwagandha might lower systolic and diastolic blood pressure. Theoretically, ashwagandha might have additive effects when used with antihypertensive drugs and increase the risk of hypotension.

Likelihood Possible Evidence D
Benzodiazepines

Theoretically, taking ashwagandha might increase the sedative effects of benzodiazepines.
There is preliminary evidence that ashwagandha might have an additive effect with diazepam (Valium) and clonazepam (Klonopin). This may also occur with other benzodiazepines.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, taking ashwagandha might increase the sedative effects of CNS depressants.
Ashwagandha seems to have sedative effects. Theoretically, this may potentiate the effects of barbiturates, other sedatives, and anxiolytics.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, taking ashwagandha with hepatotoxic drugs might increase the risk of liver damage.
Ashwagandha has been linked to cases of acute hepatitis, liver failure, hepatic encephalopathy, autoimmune hepatitis, the need for liver transplantation, and death due to liver failure.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, taking ashwagandha might decrease the effects of immunosuppressants.
Ashwagandha has demonstrated immunostimulant effects in humans. Animal research has shown that ashwagandha can attenuate the immunosuppression caused by cyclophosphamide.

Likelihood Possible Evidence D
Thyroid Hormone

Ashwagandha might increase the effects and adverse effects of thyroid hormone.
Concomitant use of ashwagandha with thyroid hormones may cause additive therapeutic and adverse effects. Preliminary clinical research and animal studies suggest that ashwagandha boosts thyroid hormone synthesis and secretion. In one clinical study, ashwagandha increased triiodothyronine (T3) and thyroxine (T4) levels by 41.5% and 19.6%, respectively, and reduced serum TSH levels by 17.4% from baseline in adults with subclinical hypothyroidism.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that ashwagandha extract induces CYP1A2 enzymes.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that ashwagandha extract induces CYP3A4 enzymes.

Likelihood Possible Evidence D
Serotonergic Drugs

Some animal studies have reported that ashwagandha can enhance serotonergic transmission by altering certain serotonin (5-HT) receptors. However, there is no evidence to suggest that ashwagandha increases the risk of serotonin-related effects, and there have been no published case reports of serotonin syndrome when combined with other serotonergic drugs. Nevertheless, due to the lack of extensive studies on the matter and the fact that ashwagandha appears to affect serotonergic pathways, it would be prudent to exercise caution when combining it with drugs that affect serotonin. [References: - Effects of Withania somnifera (Ashwaga ndha) on Stress and the Stress-Related Neuropsychiatric Disorders Anxiety, Depression, and Insomnia. Curr Neuropharmacol. 2021 Sep 14; 19: 1468–1495. - A Prospective, Randomized Double-Blind, Placebo-Controlled Study of Safety and Efficacy of a High-Concentration Full-Spectrum Extract of Ashwagandha Root in Reducing Stress and Anxiety in Adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3573577/]

Likelihood Possible Evidence C
Ashwagandha Root Extract full monograph & interactions

Coleus forskohlii Root Extract7 drug types · 915 drugs

Calcium Channel Blockers

Theoretically, combining coleus with calcium channel blockers might increase the coronary vasodilatory effects.
Forskolin, a constituent of coleus, and calcium channel blockers both cause coronary vasodilatory effects.

Likelihood Probable Evidence B
Nitrates

Theoretically, combining coleus with nitrates might increase the coronary vasodilatory effects.
Forskolin, a constituent of coleus, and nitrates both cause coronary vasodilatory effects.

Likelihood Probable Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of coleus and anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.
In vitro and animal research shows that forskolin, a constituent of coleus, can inhibit platelet aggregation and adhesion.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, combining coleus with antihypertensive drugs might cause additive blood pressure lowering effects and increase the risk of hypotension.
Animal research shows that forskolin, a constituent of coleus, may lower blood pressure.

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

Theoretically, taking coleus may affect drugs metabolized by CYP2C9 and increase the risk of adverse effects or reduce the effectiveness.
Research on the effect of coleus on CYP2C9 is conflicting. Some animal research shows that coleus extract can induce CYP2C9, while in vitro research shows that coleus can inhibit CYP2C9. Until more is known, advise patients that taking coleus might increase or decrease levels of drugs metabolized by CYP2C9.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, taking coleus might decrease serum levels of drugs metabolized by CYP3A4.
In vitro research shows that coleus can activate the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4. Although the clinical significance of this is not known, use caution when considering concomitant use of coleus and other drugs affected by these enzymes.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, taking coleus may affect the metabolism of warfarin and increase the risk of adverse effects or reduce the effectiveness.
Some animal research shows that coleus extract can induce cytochrome P450 2C9 (CYP2C9), an enzyme that metabolizes warfarin. However, other in vitro research shows that coleus can inhibit CYP2C9. Theoretically, taking coleus with drugs metabolized by CYP2C9 might affect drug levels and the risk of adverse effects. Until more is known, advise patients that taking coleus might increase or decrease levels of warfarin.

Likelihood Possible Evidence D
Coleus forskohlii Root Extract full monograph & interactions

Vitamin A4 drug types · 387 drugs

Retinoids

Concomitant use of retinoids with vitamin A supplements might produce supratherapeutic vitamin A levels.
Retinoids, which are vitamin A derivatives, could have additive toxic effects when taken with vitamin A supplements.

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, taking high doses of vitamin A in combination with other potentially hepatotoxic drugs might increase the risk of liver disease.
The tolerable upper intake level (UL) is the highest level of intake that is likely to pose no risk of adverse effects. Doses of vitamin A above the UL can cause hepatotoxicity, ranging from elevated liver enzymes to liver failure.

Likelihood Possible Evidence C
Tetracycline Antibiotics

Theoretically, taking tetracycline antibiotics with high doses of vitamin A can increase the risk of pseudotumor cerebri.
Benign intracranial hypertension (pseudotumor cerebri) can occur with tetracyclines and with acute or chronic vitamin A toxicity. Case reports suggest that taking tetracyclines and vitamin A concurrently can increase the risk of this condition. Avoid high doses of vitamin A in people taking tetracyclines chronically.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, high doses of vitamin A could increase the risk of bleeding with warfarin.
Vitamin A toxicity is associated with hemorrhage and hypoprothrombinemia, possibly due to vitamin K antagonism. Advise patients taking warfarin to avoid doses of vitamin A above the tolerable upper intake level of 10,000 IU/day for adults.

Likelihood Possible Evidence D
Vitamin A full monograph & interactions

Selenium6 drug types · 321 drugs

Anticoagulant/Antiplatelet Drugs

Selenium may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Clinical research suggests that taking selenium 10 mcg/kg/day can increase bleeding times by increasing prostacyclin production, which inhibits platelet activity. Other clinical research suggests that taking selenium 75 mcg daily, in combination with ascorbic acid 600 mg, alpha-tocopherol 300 mg, and beta-carotene 27 mg, reduces platelet aggregation.

Likelihood Possible Evidence D
Barbiturates

Theoretically, selenium might prolong the sedating effects of barbiturates.
Laboratory research suggests that selenium can inhibit the hepatic metabolism of barbiturates. Selenium seems to prolong the sedative effect of pentobarbital in animal models.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, selenium supplementation may reduce the effectiveness of immunosuppressant therapy.
In vitro research and preliminary clinical evidence suggests that selenium may stimulate the immune system.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, selenium might interfere with warfarin activity.
Animal research suggests that selenium can increase warfarin activity. Selenium might interact with warfarin by displacing it from albumin binding sites, reducing its metabolism in the liver, or by decreasing production of vitamin K-dependent clotting factors. Selenium can also prolong bleeding times in humans by increasing prostacyclin production, which inhibits platelet activity.

Likelihood Possible Evidence D
Contraceptive Drugs

Contraceptive drugs might increase levels of selenium, although the clinical significance of this effect is unclear.
Some research suggests that oral contraceptives increase serum selenium levels in women taking oral contraceptives; however, other research shows no change in selenium levels. It is suggested that an increase could be due to increased carrier proteins, indicating a redistribution of selenium rather than a change in total body selenium.

Likelihood Possible Evidence B
Niacin

Selenium might reduce the beneficial effects of niacin on high-density lipoprotein (HDL) 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 selenium, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Selenium 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

L-Tyrosine2 drug types · 21 drugs

Levodopa

Theoretically, tyrosine might decrease the effectiveness of levodopa.
Tyrosine and levodopa compete for absorption in the proximal duodenum by the large neutral amino acid (LNAA) transport system. Advise patients to separate doses of tyrosine and levodopa by at least 2 hours.

Likelihood Probable Evidence D
Thyroid Hormone

Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Tyrosine is a precursor to thyroxine and might increase levels of thyroid hormones.

Likelihood Probable Evidence D
L-Tyrosine full monograph & interactions

Vitamin B121 drug type · 20 drugs

Metformin (Glucophage)

Metformin, a common medication used to manage type 2 diabetes, has been associated with lower vitamin B12 levels in some individuals. Prolonged use of metformin can interfere with the absorption of B12 in the digestive system, potentially leading to a deficiency in this essential vitamin.

Likelihood Possible Evidence A
Vitamin B12 full monograph & interactions

Total Iodine/Iodide3 drug types · 7 drugs

Amiodarone (Cordarone)

Combining iodine with amiodarone might cause excessively high iodine levels.
Amiodarone contains 37.3% iodine and can increase iodine levels. Concomitant use with iodine might increase the risk of having excessive iodine levels and adversely affecting thyroid function. Monitor thyroid function.

Likelihood Probable Evidence D
Antithyroid Drugs

Iodine might alter the effects of antithyroid drugs.
Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking iodine while using antithyroid drugs could alter the effects of the antithyroid drugs.

Likelihood Probable Evidence D
Lithium

Combining iodine with lithium might have additive hypothyroid effects.
Lithium can inhibit thyroid function. Several case reports suggest that concomitant use of lithium and potassium iodide can reduce thyroid function in otherwise healthy adults. Monitor thyroid function.

Likelihood Probable Evidence D
Total Iodine/Iodide full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Thyroid Nutrition, from the product label.

Allergy Research Group

See all Allergy Research Group products
Name
Allergy Research Group
City
South Salt Lake
State
UT
ZipCode
84115
Phone Number
800-545-9960
Web Address
www.allergyresearchgroup.com
Pharmacist Counseling Corner

Thyroid Nutrition by Allergy Research Group: Common Questions

Does Thyroid Nutrition by Allergy Research Group interact with any medications?
Yes. Based on its ingredients, Thyroid Nutrition has a known interaction with 1,488 medications, including 38 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Thyroid Nutrition contains 8 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 on thyroid medication?
Not without checking first. L-Tyrosine and iodine may amplify or alter thyroid medication effects. Ashwagandha can also boost thyroid hormone levels. Talk to your pharmacist — timing or dose adjustments might be needed, or your thyroid levels may need monitoring.
Is this safe during pregnancy?
No. The data advises against Ashwagandha and Coleus during pregnancy due to safety concerns, and Vitamin A at high doses can cause birth defects. Iodine is necessary in pregnancy, but only in amounts your doctor recommends. Do not take this product while pregnant without explicit medical approval.
Can I take this while breastfeeding?
The safety data is not sufficient. Ashwagandha and Coleus lack breastfeeding safety data and should be avoided. Iodine can pass into breast milk in excess. Talk to your doctor or pharmacist about whether any ingredients are appropriate for you.
What are the most common side effects?
L-Tyrosine, Iodine, Selenium, and Zinc can all cause nausea, headache, and stomach upset at higher doses. Coleus commonly causes diarrhea. Ashwagandha may cause drowsiness. These are usually mild and dose-related.
Does this work for an underactive thyroid?
The ingredients support thyroid function — iodine, selenium, and tyrosine are all involved in thyroid hormone production — but the evidence that this specific product treats hypothyroidism is not established in our data. This is a support formula, not a replacement for thyroid medication. Check with your doctor.
Can I take this with antibiotics?
Not without careful timing. Zinc binds antibiotics in your gut and reduces how well they work. If you're on tetracyclines, quinolones (like ciprofloxacin), or cephalexin, separate doses by at least 2 hours (or 4–6 hours for some). Ask your pharmacist for exact timing.

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

Not sure if Thyroid Nutrition is safe with your meds?

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Ask a pharmacist

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.

Thyroid Nutrition label
Go deeper

The Full Monographs Behind Thyroid Nutrition’s Ingredients

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

Herb & supplement monograph

Tyrosine

Interacts with 21 drugs

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performance during short-term stress, sleep loss,...

Read the full Tyrosine monograph → Herb & supplement monograph

Selenium

Interacts with 321 drugs

Selenium is an essential trace mineral your body needs in small amounts for thyroid function, antioxidant defense, and immune health. Most people who eat a varied diet get enough, and supple...

Read the full Selenium monograph → Herb & supplement monograph

Vitamin B12

Interacts with 20 drugs

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very helpful for people who are deficient — su...

Read the full Vitamin B12 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

Vitamin A

Interacts with 387 drugs

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplements are mainly useful for correcting a tr...

Read the full Vitamin A monograph → Herb & supplement monograph

Ashwagandha

Interacts with 1,372 drugs

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evidence is still limited. It is generally w...

Read the full Ashwagandha monograph → Herb & supplement monograph

Coleus

Interacts with 915 drugs

Coleus is a plant from the mint family whose root contains a compound called forskolin, often marketed for weight loss, asthma, and heart health. While early lab and small human studies are...

Read the full Coleus monograph → Herb & supplement monograph

Iodine

Interacts with 7 drugs

Iodine is an essential mineral your body needs to make thyroid hormones, and most people get enough from iodized salt, dairy, and seafood. Supplements help when you are truly deficient, but...

Read the full Iodine monograph →
Sources

Sources & How We Checked

Thyroid Nutrition'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 263 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.

Tyrosine 4 references
  1. Meyer JS, Welch KM, Deshmukh VD, et al. Neurotransmitter precursor amino acids in the treatment of multi-infarct dementia and Alzheimer's disease. J Amer Geriat Soc 1977;25:289-98.
  2. DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.
  3. Wood DR, Reimherr FW, Wender PH. Amino acid precursors for the treatment of attention deficit disorder, residual type. Psychopharmacol Bull 1985;21:146-9.
  4. van Spronsen FJ, van Rijn M, Bekhof J. Phenylketonuria: tyrosine supplementation in phenylalanine-restricted diets. Am J Clin Nutr 2001;73:153-7. PubMed

See these in context on the Tyrosine monograph →

Iodine 26 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Goodman GA, Rall TW, Nies AS, Taylor P. The Pharmacological Basis of Therapeutics, 9th ed.
  3. Ghent WR, Eskin BA, Low DA, Hill LP. Iodine replacement in fibrocystic disease of the breast. Can J Surg 1993;36:453-60.
  4. Potassium iodide for nuclear exposure. Pharmacist's Letter/Prescriber's Letter 2001;17(12):171214.
  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. Cabezas C, Bustamante B, Holgado W, Begue RE. Treatment of cutaneous sporotrichosis with one daily dose of potassium iodide. Pediatr Infect Dis J 1996;15:352-4. PubMed
  7. Sterling JB, Heymann WR. Potassium iodide in dermatology: a 19th century drug for the 21st century-uses, pharmacology, adverse effects, and contraindications. J Am Acad Dermatol 2000;43:691-7. PubMed
  8. Yarrington CD, Pearce EN. Dietary iodine in pregnancy and postpartum. Clin Obstet Gynecol 2011;54:459-70. PubMed
  9. Goel, S., Mandhani, A., Srivastava, A., Kapoor, R., Gogoi, S., Kumar, A., and Bhandari, M. Is povidone iodine an alternative to silver nitrate for renal pelvic instillation sclerotherapy in chyluria? BJU.Int 2004;94(7):1082-1085. PubMed
  10. Teng, W., Shan, Z., Teng, X., Guan, H., Li, Y., Teng, D., Jin, Y., Yu, X., Fan, C., Chong, W., Yang, F., Dai, H., Yu, Y., Li, J., Chen, Y., Zhao, D., Shi, X., Hu, F., Mao, J., Gu, X., Yang, R., Tong, Y., Wang, W., Gao, T., and Li, C. Effect of iodine int
  11. Crawford, B. A., Cowell, C. T., Emder, P. J., Learoyd, D. L., Chua, E. L., Sinn, J., and Jack, M. M. Iodine toxicity from soy milk and seaweed ingestion is associated with serious thyroid dysfunction. Med J Aust. 10-4-2010;193(7):413-415. PubMed
  12. Ohkuma, M. Molluscum contagiosum treated with iodine solution and salicylic acid plaster. Int J Dermatol. 1990;29(6):443-445. PubMed
  13. Connelly KJ, Boston BA, Pearce EN, Sesser D, Snyder D, Braverman LE, Pino S, LaFranchi SH. Congenital hypothyroidism caused by excess prenatal maternal iodine ingestion. J Pediatr. 2012 Oct;161(4):760-2. PubMed
  14. Kasahara T, Narumi S, Okasora K, Takaya R, Tamai H, Hasegawa T. Delayed onset congenital hypothyroidism in a patient with DUOX2 mutations and maternal iodine excess. Am J Med Genet A. 2013 Jan;161A(1):214-7.
  15. Murcia M, Rebagliato M, Iñiguez C, Lopez-Espinosa MJ, Estarlich M, Plaza B, Barona-Vilar C, Espada M, Vioque J, Ballester F. Effect of iodine supplementation during pregnancy on infant neurodevelopment at 1 year of age. Am J Epidemiol. 2011 Apr 1;173(7):8 PubMed
  16. Sang Z, Wang PP, Yao Z, Shen J, Halfyard B, Tan L, Zhao N, Wu Y, Gao S, Tan J, Liu J, Chen Z, Zhang W. Exploration of the safe upper level of iodine intake in euthyroid Chinese adults: a randomized double-blind trial. Am J Clin Nutr. 2012 Feb;95(2):367-73 PubMed
  17. Speeckaert MM, Speeckaert R, Wierckx K, Delanghe JR, Kaufman JM. Value and pitfalls in iodine fortification and supplementation in the 21st century. Br J Nutr. 2011 Oct;106(7):964-73. PubMed
  18. Yun SE, Kang Y, Bae EJ, Hwang K, Jang HN, Cho HS, Chang SH, Park DJ. Iodine-induced thyrotoxic hypokalemic paralysis after ingestion of Salicornia herbace. Ren Fail. 2014 Apr;36(3):461-3.
  19. Iodine Hypersensitivity. Pharmacist's Letter/Prescriber's Letter 2011; 27(5):270504.
  20. Hammel JA, Selby JC. Pustular eruption in a patient with cancer treated with complementary and alternative medicine. JAMA Dermatology 2017 October; E1. doi: 10.1001/jamadermatol.2017.3749. [Epub ahead of print] PubMed
  21. Gil GS, Smith BW, Guerra JR, Williams WT. Acute Delirium in a Hypothyroid Patient Precipitated by Iodine Supplements Use. Am J Ther. 2018;25(6):e717-e718. PubMed
  22. Hamby T, Kunnel N, Dallas JS, Wilson DP. Maternal iodine excess: an uncommon cause of acquired neonatal hypothyroidism. J Pediatr Endocrinol Metab. 2018;31(9):1061-1064. PubMed
  23. Censi S, Watutantrige-Fernando S, Groccia G, et al. The Effects of Iodine Supplementation in Pregnancy on Iodine Status, Thyroglobulin Levels and Thyroid Function Parameters: Results from a Randomized Controlled Clinical Trial in a Mild-to-Moderate Iodine
  24. Rovner MS, Wolf BJ, Rubin M, et al. Instillation of 5% Povidone-Iodine Ophthalmic Drops Decreases the Respiratory Rate in Children Undergoing Strabismus Surgery: A Randomized Controlled Trial. J Pediatr Ophthalmol Strabismus. 2019;56(6):378-382. PubMed
  25. Guenezan J, Garcia M, Strasters D, et al. Povidone Iodine Mouthwash, Gargle, and Nasal Spray to Reduce Nasopharyngeal Viral Load in Patients With COVID-19: A Randomized Clinical Trial. JAMA Otolaryngol Head Neck Surg. 2021;147(4):400-401. PubMed
  26. Li F, Wan S, Zhang L, et al. A Meta-Analysis of the Effect of Iodine Excess on the Intellectual Development of Children in Areas with High Iodine Levels in their Drinking Water. Biol Trace Elem Res 2022;200(4):1580-1590. PubMed

See these in context on the Iodine monograph →

Selenium 36 references
  1. 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/.
  2. 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
  3. Trafikowska U, Zachara BA, Wiacek M, et al. Selenium supply and glutathione peroxidase activity in breastfed Polish infants. Acta Paediatr 1996;85:1143-5. PubMed
  4. Duffield-Lillico AJ, Slate EH, Reid ME, et al. Selenium supplementation and secondary prevention of nonmelanoma skin cancer in a randomized trial. J Natl Cancer Inst 2003;95:1477-81.. PubMed
  5. 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
  6. Schiavon R, Freeman GE, Guidi GC, et al. Selenium enhances prostacyclin production by cultured endothelial cells: possible explanation for increased bleeding times in volunteers taking selenium as a dietary supplement. Thromb Res 1984;34:389-96. PubMed
  7. Davila JC, Edds GT, Osuna O, Simpson CF. Modification of the effects of aflatoxin B1 and warfarin in young pigs given selenium. Am J Vet Res 1983;44:1877-83. DOI
  8. Heese HD, Lawrence MA, Dempster WS, Pocock F. Reference concentrations of serum selenium and manganese in healthy nulliparas. S Afr Med J 1988;73:163-5.
  9. Lloyd B, Lloyd RS, Clayton BE. Effect of smoking, alcohol and other factors on the selenium status of a healthy population. J Epidemiol Commun Health 1983;37:213-7. PubMed
  10. Capel ID, Jenner M, Williams DC, et al. The effect of prolonged oral contraceptive steroid use on erythrocyte glutathione peroxidase activity. J Steroid Biochem 1981;14:729-32. PubMed
  11. Contempre B, Dumont JE, Ngo B, et al. Effect of selenium supplementation in hypothyroid subjects of an iodine and selenium deficient area: the possible danger of indiscriminate supplementation of iodine-deficient subjects with selenium. J Clin Endocrinol PubMed
  12. Hofbauer LC, Spitzweg C, Magerstadt RA, Heufelder AE. Selenium-induced thyroid dysfunction. Postgrad Med J 1997;73:103-4. PubMed
  13. Debski B, Milner JA. Dietary selenium supplementation prolongs pentobarbital induced hypnosis. J Nutr Biochem 2004;15:548-53. PubMed
  14. Ishikawa M, Sasaki M, Koiwai K, et al. Inhibition of hepatic mixed-function oxidase enzymes in mice by acute and chronic treatment with selenium. J Pharmacobiodyn 1992;15:377-85. PubMed
  15. Lippmann SM, Klein EA, Goodman PJ, et al. Effect of selenium and vitamin E on risk of prostate cancer and other cancers: the selenium and vitamin E cancer prevention trial (SELECT). JAMA 2009;301:39-51. DOI
  16. Reid SM, Middleton P, Cossich MC, Crowther CA. Interventions for clinical and subclinical hypothyroidism in pregnancy. Cochrane Database Syst Rev 2010;(7):CD007752. PubMed
  17. Vinceti, M., Wei, E. T., Malagoli, C., Bergomi, M., and Vivoli, G. Adverse health effects of selenium in humans. Rev.Environ.Health 2001;16(4):233-251. PubMed
  18. Abrams, C. K., Siram, S. M., Galsim, C., Johnson-Hamilton, H., Munford, F. L., and Mezghebe, H. Selenium deficiency in long-term total parenteral nutrition. Nutr Clin Pract 1992;7(4):175-178. PubMed
  19. Spiller, H. A. and Pfiefer, E. Two fatal cases of selenium toxicity. Forensic Sci Int 8-24-2007;171(1):67-72. PubMed
  20. Negro, R., Greco, G., Mangieri, T., Pezzarossa, A., Dazzi, D., and Hassan, H. The influence of selenium supplementation on postpartum thyroid status in pregnant women with thyroid peroxidase autoantibodies. J Clin Endocrinol.Metab 2007;92(4):1263-1268. PubMed
  21. Alexander, J. Selenium. Novartis.Found.Symp 2007;282:143-149.
  22. Salonen, J. T., Salonen, R., Seppanen, K., Rinta-Kiikka, S., Kuukka, M., Korpela, H., Alfthan, G., Kantola, M., and Schalch, W. Effects of antioxidant supplementation on platelet function: a randomized pair-matched, placebo-controlled, double-blind trial
  23. Kupka, R., Mugusi, F., Aboud, S., Msamanga, G. I., Finkelstein, J. L., Spiegelman, D., and Fawzi, W. W. Randomized, double-blind, placebo-controlled trial of selenium supplements among HIV-infected pregnant women in Tanzania: effects on maternal and chil
  24. Kamble, P., Mohsin, N., Jha, A., Date, A., Upadhaya, A., Mohammad, E., Khalil, M., Pakkyara, A., and Budruddin, M. Selenium intoxication with selenite broth resulting in acute renal failure and severe gastritis. Saudi.J Kidney Dis.Transpl. 2009;20(1):106
  25. Peretz, A., Neve, J., Desmedt, J., Duchateau, J., Dramaix, M., and Famaey, J. P. Lymphocyte response is enhanced by supplementation of elderly subjects with selenium-enriched yeast. Am.J Clin.Nutr. 1991;53(5):1323-1328. PubMed
  26. Kumpulainen, J., Salmenpera, L., Siimes, M. A., Koivistoinen, P., and Perheentupa, J. Selenium status of exclusively breast-fed infants as influenced by maternal organic or inorganic selenium supplementation. Am.J Clin.Nutr. 1985;42(5):829-835. PubMed
  27. Han, L. and Zhou, S. M. Selenium supplement in the prevention of pregnancy induced hypertension. Chin Med J (Engl) 1994;107(11):870-871.
  28. Kiremidjian-Schumacher, L., Roy, M., Wishe, H. I., Cohen, M. W., and Stotzky, G. Supplementation with selenium and human immune cell functions. II. Effect on cytotoxic lymphocytes and natural killer cells. Biol.Trace Elem.Res. 1994;41(1-2):115-127. PubMed
  29. Srivastava, A. K., Gupta, B. N., Bihari, V., and Gaur, J. S. Generalized hair loss and selenium exposure. Vet.Hum.Toxicol. 1995;37(5):468-469.
  30. Sudfeld CR, Aboud S, Kupka R, et al. Effect of selenium supplementation on HIV-1 RNA detection in breast milk of Tanzanian women. Nutrition 2014;30(9):1081-4. PubMed
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  32. Thompson PA, Ashbeck EL, Roe DJ, et al. Selenium Supplementation for Prevention of Colorectal Adenomas and Risk of Associated Type 2 Diabetes. J Natl Cancer Inst. 2016;108(12). PubMed
  33. Wichman J, Winther KH, Bonnema SJ, Hegedüs L. Selenium supplementation significantly reduces thyroid autoantibody levels in patients with chronic autoimmune thyroiditis: a systematic review and meta-analysis. Thyroid 2016;26(12):1681-92. PubMed
  34. Vinceti M, Filippini T, Rothman KJ. Selenium exposure and the risk of type 2 diabetes: a systematic review and meta-analysis. Eur J Epidemiol. 2018 Sep;33(9):789-810. Epub 2018 Jul 5. Review. PubMed
  35. Fallah S, Sani FV, Firoozrai M. Effect of contraceptive pill on the selenium and zinc status of healthy subjects. Contraception. 2009;80(1):40-3. PubMed
  36. Malpas CB, Vivash L, Genc S, et al. A Phase IIa Randomized Control Trial of VEL015 (Sodium Selenate) in Mild-Moderate Alzheimer's Disease. J Alzheimers Dis. 2016;54(1):223-232. PubMed

See these in context on the Selenium monograph →

Vitamin B12 30 references
  1. 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
  2. Hartman TJ, Woodson K, Stolzenberg-Solomon R, et al. Association of the B-vitamins pyridoxal 5'-phosphate (B6), B12, and folate with lung cancer risk in older men. Am J Epidemiol 2001;153:688-94.. DOI
  3. 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..
  4. 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
  5. 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
  6. Geissbuhler, P., Mermillod, B., and Rapin, C. H. Elevated serum vitamin B12 levels associated with CRP as a predictive factor of mortality in palliative care cancer patients: a prospective study over five years. J.Pain Symptom.Manage. 2000;20(2):93-103. PubMed
  7. Salles, N., Herrmann, F., Sakbani, K., Rapin, C. H., and Sieber, C. High vitamin B12 level: a strong predictor of mortality in elderly inpatients. J Am Geriatr.Soc 2005;53(5):917-918.
  8. Looker, H. C., Fagot-Campagna, A., Gunter, E. W., Pfeiffer, C. M., Sievers, M. L., Bennett, P. H., Nelson, R. G., Hanson, R. L., and Knowler, W. C. Homocysteine and vitamin B(12) concentrations and mortality rates in type 2 diabetes. Diabetes Metab Res R
  9. Uhl, W., Nolting, A., Golor, G., Rost, K. L., and Kovar, A. Safety of hydroxocobalamin in healthy volunteers in a randomized, placebo-controlled study. Clin Toxicol (Phila) 2006;44 Suppl 1:17-28. PubMed
  10. Borron, S. W., Baud, F. J., Barriot, P., Imbert, M., and Bismuth, C. Prospective study of hydroxocobalamin for acute cyanide poisoning in smoke inhalation. Ann Emerg.Med 2007;49(6):794-801, 801. PubMed
  11. Borron, S. W., Baud, F. J., Megarbane, B., and Bismuth, C. Hydroxocobalamin for severe acute cyanide poisoning by ingestion or inhalation. Am J Emerg.Med 2007;25(5):551-558. PubMed
  12. Lewis, J. G. Gout, Steatorrhoea, and Megaloblastic Anaemia. Ann Rheum.Dis 1962;21(3):284-286. PubMed
  13. Tal, S., Shavit, Y., Stern, F., and Malnick, S. Association between vitamin B12 levels and mortality in hospitalized older adults. J Am Geriatr.Soc 2010;58(3):523-526. PubMed
  14. Baztan, J. J., Gavidia, J. J., Gomez-Pavon, J., Esteve, A., and Ruiperez, I. High vitamin B12 levels and in-hospital mortality. J Am Geriatr.Soc 2010;58(11):2237-2238. PubMed
  15. Omboni, E., Checchini, M., and Longoni, F. [Hypopotassemia and megaloblastic anemia. Presentation of a case]. Minerva Med 8-31-1987;78(16):1255-1257.
  16. Aalfs As, Scholvinck LH, Horvath B. Acneiform eruption in a 5-year old due to vitamin B12 supplementation. Eur J Dermatol 2013;23(5):726-7. PubMed
  17. Balta I, Ozuguz P. Vitamin B12-induced acneiform eruption. Cutan Ocul Toxicol 2014;33(2):94-5. PubMed
  18. Carman KB, Belgemen T, Yis U. Involuntary movements misdiagnosed as seizure during vitamin B12 treatment. Pediatr Emerg Care 2013;29(11):1223-4. PubMed
  19. Djuric V, Bogic M, Popadic AP, et al. Anaphylactic reaction to hydroxycobalamin with tolerance to cyanocobalamin. Ann Allergy Asthma Immunol 2012;108(3):207-8. PubMed
  20. Kartel O, Gulec M, Demirel F, et al. Vitamin B12 allergy and successful desensitization with cyanocobalamin: A case report. Allergol Immunopath (Madr) 2012;40(5):324-5.
  21. Patiroglu T, Unal E, Yildirim S. Infantile tremor syndrome associated with cobalamin therapy: A case report. Clin Neurol Neurosurg 2013;115(9):1903-5. PubMed
  22. Schulte S, Barkema LW, Kardaun SH. Long-lasting atypical acneiform eruption with prominent comedones induced by hydroxocobalamin (vitamin B12). J Dtsch Dermatol Ges 2014;12(6):502-3.
  23. Zanus C, Alberini E, Costa P, et al. Involuntary movements after correction of vitamin B12 deficiency: A video-case report. Epileptic Disord 2012;14(2):174-80. PubMed
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  21. Pusec CM, Wolsky R, Llerena C, Sura P. A Case of Supplement-Induced Hepatitis. Cureus 2022;14(10):e30433. PubMed
  22. Ajgaonkar A, Jain M, Debnath K. Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract for Improvement of Sexual Health in Healthy Women: A Prospective, Randomized, Placebo-Controlled Study. Cureus 2022;14(10):e30787. PubMed
  23. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  24. Lubarska M, Halasinski P, Hryhorowicz S, et al. Liver Dangers of Herbal Products: A Case Report of Ashwagandha-Induced Liver Injury. Int J Environ Res Public Health 2023;20(5):3921. PubMed
  25. Tóth M, Benedek AE, Longerich T, Seitz HK. Ashwagandha-induced acute liver injury: A case report. Clin Case Rep 2023;11(3):e7078.
  26. Bokan G, Glamocanin T, Mavija Z, et al. Herb-Induced Liver Injury by Ayurvedic Ashwagandha as Assessed for Causality by the Updated RUCAM: An Emerging Cause. Pharmaceuticals (Basel) 2023;16(8):1129. PubMed
  27. Patel PA, Sanborn E, Then R, Williams DM. Recurrent Reversible Cerebral Vasoconstriction Syndrome: A Report of Two Cases. Cureus 2023;15(8):e42992. PubMed
  28. Majeed M, Nagabhushanam K, Murali A, Vishwanathan DT, Mamidala RV, Mundkur L. A Standardized Withania somniferra (Linn.) Root Extract with Piperine Alleviates the Symptoms of Anxiety and Depression by Increasing Serotonin Levels: A Double-Blind, Randomize
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  30. Hayashi M, Hamada H, Azuma SI, Hayashi K. Painless Thyroiditis by Withania somnifera (Ashwagandha). Cureus 2024;16(3):e55352. PubMed
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See these in context on the Ashwagandha monograph →

Coleus 16 references
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  2. Kramer W, Thormann J, Kindler M, Schlepper M. Effects of forskolin on left ventricular function in dilated cardiomyopathy. Arzneimittelforschung 1987;37:364-7.
  3. Bauer K, Dietersdorfer F, Kaspar S, et al. Pharmacodynamic effects of inhaled dry powder formulations of fenoterol and colforsin in asthma. Clin Pharmacol Ther 1993;53:76-83. PubMed
  4. Christenson JT, Thulesius O, Nazzal MM. The effect of forskolin on blood flow, platelet metabolism, aggregation and ATP release. Vasa 1995;24:56-61.
  5. Agarwal KC, Zielinski BA, Maitra RS. Significance of plasma adenosine in the antiplatelet activity of forskolin: potentiation by dipyridamole and dilazep. Thromb Haemost 1989;61:106-10. DOI
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  7. Almeida, F. C. and Lemonica, I. P. The toxic effects of Coleus barbatus B. on the different periods of pregnancy in rats. J Ethnopharmacol 2000;73(1-2):53-60. PubMed
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  9. Staudinger, J. L., Ding, X., and Lichti, K. Pregnane X receptor and natural products: beyond drug-drug interactions. Expert.Opin Drug Metab Toxicol 2006;2(6):847-857. PubMed
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  14. Loftus HL, Astell KJ, Mathai ML, et al. Coleus forskohlii Extract Supplementation in Conjunction with a Hypocaloric Diet Reduces the Risk Factors of Metabolic Syndrome in Overweight and Obese Subjects: A Randomized Controlled Trial. Nutrients. 2015;7(11): PubMed
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See these in context on the Coleus monograph →

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

© 2021 Therapeutic Research Center, LLC

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