Major interaction on record — check this product against your medications before combining. Based on 9 of 10 ingredients. Check your meds →
Dietary supplement

Thyro-T Ingredients & Drug Interactions

by LifeSeasons Therapeutics

Thyro-T label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Thyro-T 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

Thyro-T is a dietary supplement by LifeSeasons Therapeutics with 10 active ingredients. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 1,484 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Sensoril, ForsLean, Guggul Resin Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Thyro-T by LifeSeasons Therapeutics

Ask about any prescription or over-the-counter medication and we check it for interactions with Thyro-T by LifeSeasons Therapeutics — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Thyro-T by LifeSeasons Therapeutics

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 10 of its 10 active ingredients.
  • “Sensoril” is listed as a grouped ingredient — the label gives one combined amount (300 mg) without saying how much of each component you get.
  • “Guggul Resin Extract” is listed as a grouped ingredient — the label gives one combined amount (100 mg) without saying how much of each component you get.
  • “ForsLean” is listed as a grouped ingredient — the label gives one combined amount (100 mg) without saying how much of each component you get.

Thyro-T contains 10 ingredients, of which several are active and traditionally used to support thyroid function. L-Tyrosine is an amino acid that serves as a building block for thyroid hormones.

Iodine and Zinc are minerals essential for thyroid health and immune function. Selenium supports thyroid hormone metabolism and antioxidant defense.

Burdock is an herb traditionally used for skin and digestive support. Forskolin (from Coleus) is thought to activate cellular processes.

Mullein is a traditional respiratory support herb. Guggulsterones, Withanolides (from Sensoril, an ashwagandha extract), and Bovine Thyroid are also included.

The product also contains inactive ingredients—Hypromellose, Microcrystalline Cellulose, and Rice Bran—which are the capsule material and fillers.

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: Support thyroid function and health.
  • We looked for evidence on: Autoimmune thyroiditis, Thyroid hormone production, Hypothyroidism, 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: Zinc is rated "Insufficient Reliable Evidence To Rate" for Autoimmune thyroiditis.

Evidence for this product's individual ingredients is mixed. L-Tyrosine is effective for a genetic condition called phenylketonuria (PKU) and possibly effective for cognitive function and memory.

Iodine is likely effective for preventing iodine deficiency and possibly effective for mouth inflammation. Zinc is effective for zinc deficiency and possibly effective for acne and age-related macular degeneration.

Selenium is likely effective for selenium deficiency and possibly effective for autoimmune thyroiditis. For the other ingredients—Burdock, Guggulsterones, Withanolides, Mullein, and Forskolin—the data we hold shows insufficient evidence or we cannot establish effectiveness for their claimed uses.

No single ingredient in this product has been proven effective specifically for supporting overall thyroid function in healthy people.

The evidence, ingredient by ingredient Tyrosine Zinc Selenium Burdock Ashwagandha Guggul Mullein Coleus

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 7 of the 7 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 7 of 7.
  • General safety write-ups exist for 7 of 7.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients are generally well tolerated at recommended doses. L-Tyrosine is generally well tolerated in healthy adults but hasn't been thoroughly studied; common mild side effects include fatigue, headache, heartburn, and nausea, especially at higher doses.

Iodine is safe in normal dietary amounts but high doses can cause thyroid problems, including too much or too little thyroid hormone. Zinc is safe below 40 mg daily; above that, long-term use may raise the risk of copper deficiency.

Selenium is safe below 400 mcg daily; excess can cause hair loss, nail changes, and rash. Burdock is likely safe for short-term use as a food but has limited human safety data; in rare cases, contact dermatitis or allergic reactions have occurred.

Mullein has limited human safety data but appears well tolerated for short-term use. Forskolin may lower blood pressure and is not well studied for long-term use.

We hold no pregnancy or lactation safety data for Guggulsterones, Withanolides, Bovine Thyroid, or Atlantic Kelp Extract. Pregnancy and lactation safety varies by ingredient—talk to your pharmacist or doctor for guidance on your individual situation.

Side effects, ingredient by ingredient Tyrosine Zinc Selenium Burdock Ashwagandha Guggul Mullein Coleus

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?
  • 7 of the 7 matched ingredients can interact with medications — Iodine, Burdock, Mullein, Zinc, Selenium, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; lithium; Parkinson's medications.
  • For scale: 1,121 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.

Check with your pharmacist before taking Thyro-T if you use any of these: nitrates or calcium channel blockers for heart disease (Major risk); blood pressure medications, blood thinners (warfarin, aspirin), or anticoagulants; antibiotics (quinolones, tetracyclines, cephalexin); penicillamine for rheumatoid arthritis; HIV medications (ritonavir, integrase inhibitors, bictegravir-based drugs); lithium for bipolar disorder; antithyroid drugs or thyroid hormone replacements; the heart rhythm drug amiodarone; levodopa for Parkinson's; cisplatin for cancer; barbiturates for seizures; or contraceptives. No interactions are documented for Guggulsterones, Withanolides, Bovine Thyroid, or Atlantic Kelp Extract because we hold no data for them.

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.

Thyro-T is intended to support thyroid function using a blend of minerals, amino acids, and herbs. It's most appropriate for people with documented deficiencies in iodine, zinc, or selenium, or those whose doctor has advised thyroid support.

You should be especially careful if you take heart or blood pressure medications, blood thinners, antibiotics, HIV drugs, or thyroid replacements—all of which this product can affect. Before starting, check your medications against the tool on this page and discuss it with your pharmacist or doctor.

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

Assessment coverage: 7 of 10 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 25, 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 Thyro-T, straight from the product label.

Brand LifeSeasons Therapeutics
Barcode (UPC) 853760002216
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jul 25, 2024
DSLD ID 310526
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, 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 Thyro-T by LifeSeasons Therapeutics, 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
30
UPC/BARCODE
853760002216
IngredientAmount% DV
L-Tyrosine200 mg--
Iodine1.75 mcg--
Zinc5 mg45%
Selenium50 mcg91%
Burdock25 mg--
Guggulsterones2.5 mg--
Sensoril300 mg--
Withanolides30 mg--
Guggul Resin Extract100 mg--
Mullein50 mg--
Forskolin10 mg--
ForsLean100 mg--
Bovine Thyroid50 mg--
Atlantic Kelp Extract43 mg--

Other ingredients: Hypromellose, Microcrystalline Cellulose, Rice Bran

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

Take 2 capsules daily, with or without food.

Precautions

Caution: For adults. Keep out of reach of children.

Use only as directed. Tamper evident. Do not use if printed safety seal under cap is broken or missing.

If pregnant, nursing, taking medication, or under medical supervision for any condition, consult a healthcare professional before use.

Storage

Store in a cool, dry place.

Formulation

Gluten-Free. No artificial colors, flavors, preservatives, yeast, eggs, fish, shellfish, peanuts, tree nuts, wheat, milk, or magnesium stearate

Made in USA with globally sourced ingredients.

Thyro-T helps support healthy thyroid function, hormone balance, energy, and stress control

Thyroid support

Brand IP Statement(s)

Copyright 2022

Formula

L-Tyrosine is a stimulating amino acid and precursor to thyroid hormone Ashwagandha (Sensoril) supports thyroid health and stress management Thyroid bovine glandular (hormone-free) supports thyroid function Coleus Forskohlii (Forslean) helps promote metabolic processes Kelp is a natural source of iodine that is needed for thyroid function

Coleus Forskohlii Ashwagandha L-Tyrosine Thyroid Kelp

FDA Disclaimer Statement

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

FDA Statement of Identity

Dietary Supplement

General Statements

Questions? (877) 455-2826 or www.lifeseasons.com

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

See for yourself

Thyro-T by LifeSeasons Therapeutics label

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

Thyro-T 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 Thyro-T by LifeSeasons Therapeutics

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

Serving size2 Capsule(s) Dosage formCapsule Servings per container30 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
200 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

Zinc

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

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

Selenium

Interacts with
321 drugs
50 mcg per serving Form: L-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

Burdock

Interacts with
122 drugs
25 mg per serving

Burdock is a traditional herb most often used for skin problems and as a so-called 'blood purifier,' but high-quality human studies are lacking and mo...

Burdock monograph & interactions

Sensoril

Interacts with
1,372 drugs
300 mg per serving Form: Ashwagandha Leaf, Root Extract

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...

Sensoril monograph & interactions
  • › Withanolides

Guggul Resin Extract

Interacts with
757 drugs
100 mg per serving

Guggul is a gum resin from the Commiphora wightii tree, long used in Ayurvedic medicine for cholesterol, joint, and skin problems. Modern studies are...

Guggul Resin Extract monograph & interactions
  • › Guggulsterones

Mullein

Interacts with
122 drugs
50 mg per serving Form: Verbascum thapsus

Mullein is a traditional herbal remedy most often used as a tea or syrup to soothe coughs, sore throats, and respiratory irritation. High-quality huma...

Mullein monograph & interactions

ForsLean

Interacts with
915 drugs
100 mg per serving Form: Coleus forskohlii Root Extract

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...

ForsLean monograph & interactions

Bovine Thyroid

50 mg per serving

Atlantic Kelp Extract

43 mg per serving Form: Laminaria digitata Extract

Other (inactive) ingredients: Hypromellose, Microcrystalline Cellulose, Rice Bran. These complete the product’s ingredient list but are not active constituents.

Interaction report

Thyro-T by LifeSeasons Therapeutics Drug Interactions

Want to check YOUR meds against Thyro-T?

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
1,484Drugs
29 Major 1,386 Moderate 69 Minor

Ingredients driving the most interactions

Sensoril 1,372
ForsLean 915
Guggul Resin Extract 757
Selenium 321
Burdock 122

Individual Drug Interactions

The ingredients in Thyro-T interact with 1,484 drugs. Click any drug to see the details.

9 of the 10 ingredients in Thyro-T interact with drugs. Each result below shows which ingredient is responsible. Sensoril ForsLean Guggul Resin Extract Selenium Burdock Mullein Zinc L-Tyrosine Iodine

Each ingredient & the kinds of drugs it affects

For each ingredient in Thyro-T 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.

Sensoril10 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
Sensoril full monograph & interactions

ForsLean7 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
ForsLean full monograph & interactions

Guggul Resin Extract9 drug types · 757 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, guggul might increase the risk of bleeding when taken with anticoagulant/antiplatelet drugs.
In vitro research and preliminary clinical studies suggest that guggul might have antiplatelet and anticoagulant effects.

Likelihood Possible Evidence B
Contraceptive Drugs

Theoretically, guggul might increase the risk of adverse effects when taken with contraceptive drugs.
In vitro research shows that guggul has estrogen-alpha receptor agonist activity.

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

Theoretically, guggul might reduce the effects of CYP3A4 substrates.
In vitro research shows that guggul constituents known as guggulsterones can induce CYP3A4.

Likelihood Probable Evidence D
Diltiazem (Cardizem, Others)

Guggul might reduce the effects of diltiazem.
A small pharmacokinetic study shows that concomitant use of guggul with diltiazem reduces the bioavailability of diltiazem.

Likelihood Probable Evidence B
Estrogens

Theoretically, guggul might increase the risk of adverse effects when taken with estrogens.
In vitro research shows that guggul constituents known as guggulsterones have estrogen-alpha receptor agonist activity.

Likelihood Possible Evidence D
Propranolol (Inderal)

Guggul might reduce the effects of propranolol.
A small pharmacokinetic study shows that concomitant use of guggul with propranolol reduces the bioavailability of propranolol.

Likelihood Probable Evidence B
Rosuvastatin (Crestor)

Theoretically, guggul might increase the effects and adverse effects of rosuvastatin.
Animal research shows that guggul increases the bioavailability and hypolipidemic effects of rosuvastatin. The mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, guggul might interfere with tamoxifen therapy.
In vitro research shows that guggul has estrogen-alpha receptor agonist activity.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, guggul might increase the risk for adverse effects when taken with thyroid hormone therapy.
Animal research suggests that guggul has thyroid-stimulating effects.

Likelihood Probable Evidence B
Guggul Resin Extract 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

Burdock1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, taking burdock with anticoagulant or antiplatelet drugs might increase the risk of bleeding.

In vitro research shows that lignans from burdock reduce rabbit platelet aggregation by inhibiting platelet activating factor. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Burdock full monograph & interactions

Mullein1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Lab tests on extracts from different parts of common and dense-flowered mullein plants show that they do have some blood-thinning effects, as they increase the time it takes for blood to clot. This is likely due to at least one of the known constituents of muellein, triterpenoid saponins. However, the effects appear to be mild and results have been inconsistent. Extracts from different plant parts have been show to have varying anticoagulant strengths, with water-based ones being more potent than alcohol-based extracts.

Likelihood Unlikely Evidence A
Mullein 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

Iodine3 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
Iodine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Thyro-T, from the product label.

LifeSeasons Therapeutics

See all LifeSeasons Therapeutics products
Name
LifeSeasons
City
Kaysville
State
UT
ZipCode
84037
Phone Number
(877) 455-2826
Web Address
www.lifeseasons.com
Pharmacist Counseling Corner

Thyro-T by LifeSeasons Therapeutics: Common Questions

Does Thyro-T by LifeSeasons Therapeutics interact with any medications?
Yes. Based on its ingredients, Thyro-T has a known interaction with 1,484 medications, including 29 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Thyro-T contains 10 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is Thyro-T safe to take while pregnant?
The safety data varies by ingredient. Iodine in amounts your doctor advises is important in pregnancy, but avoid high-dose products. Burdock and Mullein should be avoided during pregnancy due to lack of safety data. Zinc and Selenium have mixed ratings—Zinc is rated likely safe, but Selenium is possibly unsafe. We hold no pregnancy data for Guggulsterones, Withanolides, Bovine Thyroid, or Atlantic Kelp Extract. Talk to your doctor or pharmacist before taking this during pregnancy.
Can I take Thyro-T while breastfeeding?
Again, it depends on the ingredient. Iodine in normal amounts is acceptable but avoid excess since it passes into breast milk. Zinc is likely safe while breastfeeding. Selenium and L-Tyrosine have limited data—there isn't enough information to know if they're safe. Burdock and Mullein are best avoided. We hold no breastfeeding data for Guggulsterones, Withanolides, Bovine Thyroid, or Atlantic Kelp Extract. Ask your doctor or pharmacist for personalized guidance.
What does L-Tyrosine do?
L-Tyrosine is an amino acid your body uses to make thyroid hormones and neurotransmitters that affect mood and focus. It's proven effective for a rare genetic condition called PKU and possibly helpful for memory and thinking, though evidence for general thyroid support is not established in the data we hold.
Will Thyro-T help my thyroid if I don't have a deficiency?
The evidence we hold doesn't show that Thyro-T or its individual ingredients are effective for supporting overall thyroid function in people without a documented deficiency. If you suspect a thyroid problem, get tested first—a doctor can determine whether you need supplementation and what dose.
What are the most common side effects?
L-Tyrosine may cause fatigue, headache, heartburn, or nausea, especially at higher doses. Iodine can cause metallic taste, nausea, or headache. Zinc may cause nausea, diarrhea, or abdominal cramps. Selenium may cause headache or rash. Forskolin can cause diarrhea, nausea, or constipation. Most side effects are mild and dose-related.
Can I take Thyro-T with my thyroid medication?
L-Tyrosine in Thyro-T theoretically may have additive effects with thyroid hormone medications, potentially boosting their effects. Iodine can also alter how thyroid medications work. Do not take this product with thyroid replacements without talking to your doctor first—your dose may need adjustment, and your thyroid function should be monitored.

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.

Thyro-T label
Go deeper

The Full Monographs Behind Thyro-T’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

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

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

Burdock

Interacts with 122 drugs

Burdock is a traditional herb most often used for skin problems and as a so-called 'blood purifier,' but high-quality human studies are lacking and most claims are not well proven. It is wid...

Read the full Burdock 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

Guggul

Interacts with 757 drugs

Guggul is a gum resin from the Commiphora wightii tree, long used in Ayurvedic medicine for cholesterol, joint, and skin problems. Modern studies are mixed and often low-quality, and it can...

Read the full Guggul monograph → Herb & supplement monograph

Mullein

Interacts with 122 drugs

Mullein is a traditional herbal remedy most often used as a tea or syrup to soothe coughs, sore throats, and respiratory irritation. High-quality human studies are lacking, so its benefits a...

Read the full Mullein 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

Thyro-T'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 236 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 →

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
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Guggul 21 references
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  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
  6. Agarwal KC, Parks RE. Forskolin: a potential antimetastatic agent. Int J Cancer 1983;32:801-4. PubMed
  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
  8. Ding, X. and Staudinger, J. L. Induction of drug metabolism by forskolin: the role of the pregnane X receptor and the protein kinase a signal transduction pathway. J Pharmacol Exp Ther 2005;312(2):849-856. PubMed
  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
  10. van Hecke, E., Hindryckx, P., Geuns, J. M., and Devriese, E. Airborne contact dermatitis from coleus in a housewife. Contact Dermatitis 1991;25(2):128-129. PubMed
  11. Schlepper, M., Thormann, J., and Mitrovic, V. Cardiovascular effects of forskolin and phosphodiesterase-III inhibitors. Basic Res Cardiol 1989;84 Suppl 1:197-212. PubMed
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  13. Lindner, E., Dohadwalla, A. N., and Bhattacharya, B. K. Positive inotropic and blood pressure lowering activity of a diterpene derivative isolated from Coleus forskohli: Forskolin. Arzneimittelforschung 1978;28(2):284-289.
  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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  16. Nishijima C, Chiba T, Sato Y, Umegaki K. Nationwide Online Survey Enables the Reevaluation of the Safety of Coleus forskohlii Extract Intake Based on the Adverse Event Frequencies. Nutrients. 2019;11(4). pii: E866. PubMed

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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