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

Thyroid-SP Ingredients & Drug Interactions

by Bronson

Thyroid-SP 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 Thyroid-SP 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-SP is a dietary supplement by Bronson with 4 active ingredients. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 1,456 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ashwagandha, Coleus forskohlii extract, L-Tyrosine. 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-SP by Bronson

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

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HelloPharmacist Scorecard of Thyroid-SP by Bronson

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 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Thyroid-SP contains 4 active ingredients. L-Tyrosine is an amino acid your body uses to build thyroid hormone; it's been shown effective for a genetic disorder called PKU and possibly helpful for memory and mental focus.

Iodine is an essential mineral and a core building block of thyroid hormone, proven effective for iodine deficiency and radiation exposure protection. Ashwagandha is an herbal adaptogen used traditionally to help with stress, anxiety, and sleep — the evidence supports it as possibly effective for those purposes.

Coleus forskohlii extract contains forskolin, a compound studied for heart and breathing conditions, though evidence for its effectiveness in those areas is not yet established. The product also contains inactive ingredients: gelatin (capsule shell), microcrystalline cellulose, magnesium stearate, and silicon dioxide.

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: supports healthy thyroid function metabolism energy.
  • We looked for evidence on: Cognitive function, Fatigue, Hypothyroidism, Iodine deficiency, Memory, Stress — and 4 related terms.
  • The strongest evidence on file: Iodine is rated "Likely Effective" for Iodine deficiency (Natural Medicines).
  • Also on file: Ashwagandha is rated "Possibly Effective" for Anxiety, Generalized anxiety disorder (GAD), Stress.
  • Also on file: Tyrosine is rated "Possibly Effective" for Cognitive function, Memory.

L-Tyrosine is effective for phenylketonuria (PKU) and possibly effective for cognitive function and memory. Iodine is likely effective for preventing iodine deficiency and protecting against radiation exposure, and possibly effective for oral inflammation and gum disease.

Ashwagandha is possibly effective for insomnia, anxiety, stress, and generalized anxiety disorder. For Coleus forskohlii extract, the evidence is not yet established in our data for any condition — we hold insufficient reliable evidence to rate its effectiveness.

The evidence, ingredient by ingredient Tyrosine Iodine Ashwagandha 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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-Tyrosine is generally well tolerated in healthy adults, though not enough long-term safety data exists; talk to a healthcare provider before regular use. Most side effects are mild — fatigue, headache, heartburn, nausea — and more common at higher doses.

Iodine is safe in normal dietary amounts, but high doses can cause thyroid problems; it's important in pregnancy and breastfeeding but must be used only at the dose your doctor advises. Ashwagandha is generally well tolerated short-term, but quality and long-term safety data are limited; it's traditionally thought to risk miscarriage, so the safety data advises against it in pregnancy, and there isn't enough data to know if it's safe while breastfeeding.

Coleus may lower blood pressure and is not well studied long-term; the safety data advises against use in pregnancy and breastfeeding. A small number of cases have linked ashwagandha to serious liver problems and, rarely, to a type of reversible brain vessel constriction.

Iodine in very high amounts has rarely caused severe allergic reactions. These are uncommon, but if you develop severe abdominal pain, yellowing of skin or eyes, unusual bleeding, or sudden severe headache and vision changes, stop and seek medical care.

Side effects, ingredient by ingredient Tyrosine Iodine Ashwagandha 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?
  • 4 of the 4 matched ingredients can interact with medications — Iodine, Ashwagandha, Tyrosine, Coleus.
  • 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: 1,457 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 your medications against this product if you take nitrates or calcium channel blockers (Major severity risk). Also double-check if you take thyroid hormones, blood pressure medicines, blood thinners or antiplatelet drugs, blood sugar medications, sedatives or benzodiazepines, lithium, amiodarone, or any drug metabolized by your liver — all carry Moderate-severity interactions with one or more ingredients here.

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.

Thyroid-SP may be right for you if you're looking to support thyroid health with iodine and tyrosine, and you also want the adaptogenic benefits of ashwagandha. But if you take any heart, blood pressure, blood sugar, sleep, or psychiatric medications — or lithium, amiodarone, or warfarin — you need to check this product against your exact medications first.

Talk to your pharmacist before you start, especially if you have thyroid disease, liver disease, or are pregnant or breastfeeding.

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

Assessment coverage: 4 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 23, 2020.

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

At a glance

General information

Key facts about Thyroid-SP, straight from the product label.

Brand Bronson
Barcode (UPC) 716563372026
Net contents 180 Capsule(s)
Market status On market
Date entered into DSLD Aug 23, 2020
DSLD ID 233146
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses 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-SP by Bronson, 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 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
180
UPC/BARCODE
716563372026
IngredientAmount% DV
L-Tyrosine200 mg--
Iodine300 mcg200%
Ashwagandha50 mg--
Coleus forskohlii extract10.8 mg--

Other ingredients: Gelatin, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide

Tap any ingredient to jump to its full detail below.

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

Bronson Nutrition+ since 1960

180 Count

Discover the Bronson Difference To Reorder: www.bronsonvitamins.com 1-800-235-3200

Formulation

Helps support healthy thyroid function Helps maintain healthy metabolism, circulation, and energy

Suggested/Recommended/Usage/Directions

Take 1-3x daily

Directions: As a dietary supplement for adults, take 1 capsule one to three times daily or as directed by a healthcare professional.

FDA Statement of Identity

Dietary Supplement

Formula

300 mcg Iodine 200 mcg L-Tyrosine 50 mg Ashwagandha

Precautions

Warning: Consult a healthcare professional before taking this product if you are pregnant or nursing.

Keep out of reach of children.

Storage

Store at room temperature. Protect from light.

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.

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

See for yourself

Thyroid-SP by Bronson label

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

Thyroid-SP 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-SP by Bronson

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container180 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

Iodine

Interacts with
7 drugs
300 mcg per serving Form: Kelp

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

Iodine monograph & interactions

Ashwagandha

Interacts with
1,372 drugs
50 mg per serving

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 monograph & interactions

Coleus forskohlii extract

Interacts with
915 drugs
10.8 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 extract monograph & interactions

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

Interaction report

Thyroid-SP by Bronson Drug Interactions

Want to check YOUR meds against Thyroid-SP?

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
1,456Drugs
29 Major 1,356 Moderate 71 Minor

Ingredients driving the most interactions

Ashwagandha 1,372
Coleus forskohlii extract 915
L-Tyrosine 21
Iodine 7

Individual Drug Interactions

The ingredients in Thyroid-SP interact with 1,456 drugs. Click any drug to see the details.

4 of the 4 ingredients in Thyroid-SP interact with drugs. Each result below shows which ingredient is responsible. Ashwagandha Coleus forskohlii extract L-Tyrosine Iodine

Each ingredient & the kinds of drugs it affects

For each ingredient in Thyroid-SP 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.

Ashwagandha10 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 full monograph & interactions

Coleus forskohlii 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 extract 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 Thyroid-SP, from the product label.

Bronson

Name
Bronson Laboratories
Street Address
350 South 400 West #102
City
Lindon
State
UT
ZipCode
84042
Phone Number
1-800-235-3200
Web Address
www.bronsonvitamins.com
Pharmacist Counseling Corner

Thyroid-SP by Bronson: Common Questions

Does Thyroid-SP by Bronson interact with any medications?
Yes. Based on its ingredients, Thyroid-SP has a known interaction with 1,456 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?
Thyroid-SP contains 4 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?
No — not without checking with your pharmacist first. Both L-Tyrosine and Ashwagandha can add to the effects of thyroid hormone medications, and Iodine interacts with thyroid drugs too. Your pharmacist needs to review your specific thyroid medicine and dose to see if this product is safe for you.
Is ashwagandha in here safe during pregnancy?
No. The safety data advises against ashwagandha in pregnancy because it's traditionally thought to carry a miscarriage risk. Iodine is important in pregnancy, but only at the dose your doctor recommends, not from a supplement like this. Talk to your doctor or midwife before taking any of these ingredients while pregnant.
What are the most common side effects?
L-Tyrosine can cause fatigue, headache, heartburn, or nausea. Iodine may cause headache, nausea, or a metallic taste. Ashwagandha can cause diarrhea, nausea, vomiting, or drowsiness. Coleus may cause diarrhea, constipation, nausea, or vomiting. These are usually mild and often dose-related.
Does this actually help with thyroid function?
L-Tyrosine and Iodine are both building blocks your body needs to make thyroid hormone, and iodine is proven effective for iodine deficiency. Ashwagandha may support thyroid hormone production, but we don't have established evidence that this combination works as a thyroid support product. Your best bet is to talk with your doctor about whether you need supplemental iodine or tyrosine for your specific situation.
Can I take this with my blood pressure medicine?
Maybe, but you need to check first. Ashwagandha and Coleus can both lower blood pressure, so taking them together with a blood pressure drug could drop your pressure too far. Your pharmacist can tell you if the combination is safe or if you need monitoring.
What is Coleus forskohlii extract supposed to do?
Coleus contains a compound called forskolin that's been studied for heart health, asthma, and other conditions, but we don't have enough reliable evidence yet to say it actually works for any of those uses. It's included in this product likely because of its traditional use, but its effectiveness is not established.

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.

Thyroid-SP label
Go deeper

The Full Monographs Behind Thyroid-SP’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

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 → 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 →
Sources

Sources & How We Checked

Thyroid-SP'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 78 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
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Ashwagandha 32 references
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Coleus 16 references
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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