Bladderwrack Thallus Ingredients & Drug Interactions
What is this page for?
First and foremost: checking Bladderwrack Thallus 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
Bladderwrack Thallus is a dietary supplement by Nature's Answer with 1 active ingredient. Its ingredients are commonly taken for thyroid support, iodine source, weight management.Based on those ingredients, 891 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Bladderwrack Thallus Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Bladderwrack Thallus by Nature's Answer
Ask about any prescription or over-the-counter medication and we check it for interactions with Bladderwrack Thallus by Nature's Answer — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Bladderwrack Thallus by Nature's Answer
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.
What’s inside
Full disclosure
This supplement contains one active ingredient: iodine from bladderwrack thallus extract. Iodine is a mineral your body needs for thyroid and metabolism support.
The liquid also includes vegetable glycerin and purified water as inactive ingredients to deliver the iodine in liquid form.
Does it work?
Strong evidence
Iodine is likely effective for preventing or treating iodine deficiency and for protecting the thyroid after radiation exposure. It's possibly effective for oral mouth sores (mucositis) and gum disease (periodontitis), though the evidence for those uses is less established in our data.
How safe is it?
Well-documented data
Iodine is generally well tolerated in normal dietary amounts, but high doses can cause thyroid problems — including an underactive thyroid, an overactive thyroid, or thyroid nodules. Common side effects from larger doses include nausea, diarrhea, abdominal upset, headache, and a metallic taste.
Rare but serious reactions include severe allergic responses. In pregnancy, adequate iodine is important, but use only the amount your doctor advises and avoid high-dose products.
Some iodine passes into breast milk, so follow your doctor's guidance while breastfeeding.
Meds to double-check
Moderate interaction found
Check with your pharmacist if you take lithium, antithyroid drugs (like methimazole or propylthiouracil), or amiodarone (Cordarone). All three interact with iodine at a Moderate level and require monitoring of thyroid function.
The bottom line
Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
This supplement is useful if you're deficient in iodine or need thyroid protection after radiation. If you take lithium, antithyroid drugs, or amiodarone, talk to your pharmacist or doctor first — your thyroid function may need monitoring.
For anyone else, check your exact medications with the tool on this page before starting.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 19, 2022.
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
General information
Key facts about Bladderwrack Thallus, straight from the product label.
| Brand | Nature's Answer |
|---|---|
| Barcode (UPC) | 083000001390 |
| Net contents | 1 fl. Oz.; 30 mL |
| Market status | On market |
| Date entered into DSLD | May 19, 2022 |
| DSLD ID | 263920 |
| Product type | Botanical |
| Supplement form | Liquid |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Kosher, Women (not pregnant or lactating), Gluten Free |
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 Bladderwrack Thallus by Nature's Answer, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Iodine | 60 mcg | -- |
| Bladderwrack Thallus Extract | 1000 mg | -- |
Other ingredients: Vegetable Glycerin, Water, Purified
Tap any ingredient to jump to its full detail below.
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.
FDA Disclaimer Statement
This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
Formulation
Gluten Free
Promotes healthy thyroid function
Low Organic Alcohol 12-15% 12-15% by volume certified organic alcohol.
Our alcohol-free extracts are produced using our cold Bio-Chelated proprietary extraction process, yielding a Holistically Balanced Advanced Botanical Fingerprint extract in the same synergistic ratios as in the plant.
Formula
K Parve (Kosher)
60 mcg Iodine per serving
Seals/Symbols
K Parve (Kosher)
Bio-Chelated Cold Extraction Process
FDA Statement of Identity
Herbal Supplement
Brand IP Statement(s)
Nature's Answer Since 1972
Discover Nature's Answer
Copyright 2020 Nature's Answer
Suggested/Recommended/Usage/Directions
Suggested Use: As a dietary supplement, take 1/2-1 mL (19-39 drops) three (3) times a day in a small amount of water. Shake well.
Precautions
Keep out of reach of children.
Warning: Do not use if pregnant or nursing.
Do not use if safety seal is damaged or missing.
Storage
Store in a cool, dry place.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Bladderwrack Thallus by Nature's Answer label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Bladderwrack Thallus by Nature's Answer
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size0.5 mL Dosage formLiquid Servings per container30 Amounts shown are per serving.
Bladderwrack Thallus Extract
Interacts with891 drugs
Fucus vesiculosus (bladderwrack) is a brown seaweed rich in iodine that has been used traditionally for thyroid concerns, weight, and skin. There is l...
Bladderwrack Thallus Extract monograph & interactions- › Iodine
Other (inactive) ingredients: Vegetable Glycerin, Water, Purified. These complete the product’s ingredient list but are not active constituents.
Bladderwrack Thallus by Nature's Answer Drug Interactions
HelloPharmacist Interaction Report
Bladderwrack Thallus by Nature's Answer is a single-ingredient liquid supplement containing iodine, and it does interact with several medications.
The most serious concern is with lithium (used for mood disorders), where iodine may add to lithium's ability to slow thyroid function. Both drugs can lower thyroid activity on their own, and together they raise the risk — your thyroid function should be monitored if you take both.
Read the full breakdown — every affected drug type, severity by severity
Iodine also interacts with antithyroid drugs (used to treat overactive thyroid) in a Moderate way. High-dose iodine can flip between causing an overactive thyroid or an underactive one depending on your history, so it may interfere with how your antithyroid medication works.
Similarly, amiodarone (Cordarone), a heart rhythm drug that's already very high in iodine, can combine with this supplement to push your iodine levels too high and damage thyroid function.
Altogether, these interactions span 7 individual medications. Use the medication checker on this page to see if any of your prescriptions are affected before you start.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Bladderwrack Thallus?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Bladderwrack Thallus interact with 891 drugs. Click any drug to see the details.
1 of the 1 ingredient in Bladderwrack Thallus interact with drugs. Each result below shows which ingredient is responsible. Bladderwrack Thallus Extract
AmiodaroneCordarone, Pacerone
How Amiodarone interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 2c8 (cyp2c8) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP2C8 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Amiodarone interactionIodineAmiodarone (cordarone) Moderate
Interaction Summary
Combining iodine with amiodarone might cause excessively high iodine levels.
Read the full Iodine + Amiodarone interactionCarbimazoleNeo-Mercazole
How Carbimazole interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
IodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Carbimazole interactionBladderwrack Thallus ExtractAntithyroid Drugs Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Read the full Bladderwrack Thallus Extract + Carbimazole interactionConjugated EstrogensCenestin, Enjuvia, Premarin, Premarin Vaginal Cream
How Conjugated Estrogens interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Thyroid Hormone Moderate
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Conjugated Estrogens interactionDesiccated Thyroid ExtractWesthroid, WP Thyroid
How Desiccated Thyroid Extract interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Desiccated Thyroid Extract interactionDesiccated Thyroid Extract (prescription Drug)Nature-Throid, Thyrar
How Desiccated Thyroid Extract (prescription Drug) interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Desiccated Thyroid Extract (prescription Drug) interactionDextrothyroxineCholoxin
How Dextrothyroxine interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Dextrothyroxine interactionHuman Chorionic Gonadotropin (hcg)Pregnyl
How Human Chorionic Gonadotropin (hcg) interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Human Chorionic Gonadotropin (hcg) interactionLevothyroxineEltroxin, Estre, Euthyrox, Levo-T, Levolet, Levothroid +5 more
How Levothyroxine interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Levothyroxine interactionLevothyroxine SodiumErmez, Thyquidity, Tirosint-Sol
How Levothyroxine Sodium interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Levothyroxine Sodium interactionLevothyroxine, LiothyronineArmour Thyroid
How Levothyroxine, Liothyronine interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Levothyroxine, Liothyronine interactionLiothyronineCytomel
How Liothyronine interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Liothyronine interactionLiotrixEuthroid 1, Euthroid 1/2, Euthroid 3
How Liotrix interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Liotrix interactionLiotrix, T4/t3Euthroid 2
How Liotrix, T4/t3 interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Liotrix, T4/t3 interactionLithium Carbonate (prescription Drug)Eskalith, Lithium Carbonate
How Lithium Carbonate (prescription Drug) interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
IodineLithium Moderate
Interaction Summary
Combining iodine with lithium might have additive hypothyroid effects.
Read the full Iodine + Lithium Carbonate (prescription Drug) interactionBladderwrack Thallus ExtractLithium Moderate
Interaction Summary
Concomitant use of Fucus vesiculosus and lithium has resulted in hyperthyroidism.
Read the full Bladderwrack Thallus Extract + Lithium Carbonate (prescription Drug) interactionMenotropinsMenopur, Repronex
How Menotropins interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Menotropins interactionMethenamine MandelateMandelamine, Methimazole
How Methenamine Mandelate interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
IodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Methenamine Mandelate interactionBladderwrack Thallus ExtractAntithyroid Drugs Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Read the full Bladderwrack Thallus Extract + Methenamine Mandelate interactionMethimazoleTapazole
How Methimazole interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractAntithyroid Drugs Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Read the full Bladderwrack Thallus Extract + Methimazole interactionIodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Methimazole interactionOspemifeneOsphena
How Ospemifene interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Thyroid Hormone Moderate
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Ospemifene interactionPotassium Iodide (prescription Drug)Thyro-Block
How Potassium Iodide (prescription Drug) interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
IodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Potassium Iodide (prescription Drug) interactionBladderwrack Thallus ExtractAntithyroid Drugs Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Read the full Bladderwrack Thallus Extract + Potassium Iodide (prescription Drug) interactionPropylthiouracil, PtuPropylthiouracil
How Propylthiouracil, Ptu interacts with Bladderwrack Thallus — through 2 ingredients. Tap an ingredient for the detail:
IodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Propylthiouracil, Ptu interactionBladderwrack Thallus ExtractAntithyroid Drugs Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Read the full Bladderwrack Thallus Extract + Propylthiouracil, Ptu interactionTestosterone UndecanoateAndriol, Aveed, Jatenzo, Kyzatrex
How Testosterone Undecanoate interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Thyroid Hormone Moderate
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Testosterone Undecanoate interactionThyroglobulinProloid
How Thyroglobulin interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Thyroglobulin interactionThyroid HormoneEtwon
How Thyroid Hormone interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractThyroid Hormone Moderate
Interaction Summary
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Read the full Bladderwrack Thallus Extract + Thyroid Hormone interactionAdo-trastuzumab EmtansineKadcyla
How Ado-trastuzumab Emtansine interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Ado-trastuzumab Emtansine interactionAbciximabReoPro
How Abciximab interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractAnticoagulant/antiplatelet Drugs Minor
Interaction Summary
Theoretically, taking Fucus vesiculosus with antiplatelet or anticoagulant drugs might increase the risk of bruising and bleeding.
Read the full Bladderwrack Thallus Extract + Abciximab interactionAbemaciclibVerzenio
How Abemaciclib interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Abemaciclib interactionAbiraterone
How Abiraterone interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Abiraterone interactionAbiraterone AcetateYonsa, Zytiga
How Abiraterone Acetate interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Abiraterone Acetate interactionAbrocitinibCibinqo
How Abrocitinib interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractAnticoagulant/antiplatelet Drugs, Cytochrome P450 2c9 (cyp2c9) Substrates Minor
Interaction Summary
Theoretically, taking Fucus vesiculosus with antiplatelet or anticoagulant drugs might increase the risk of bruising and bleeding.
Read the full Bladderwrack Thallus Extract + Abrocitinib interactionAcalabrutinibCalquence
How Acalabrutinib interacts with Bladderwrack Thallus — through 1 ingredient. Tap an ingredient for the detail:
Bladderwrack Thallus ExtractCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
Read the full Bladderwrack Thallus Extract + Acalabrutinib interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Bladderwrack Thallus with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.
Bladderwrack Thallus Extract
Amiodarone (Cordarone)
Theoretically, combining Fucus vesiculosus with amiodarone might cause excessively high iodine levels.
Fucus vesiculosus contains high concentrations of iodine. Amiodarone contains 37.3% iodine and can increase iodine levels. Concomitant use might increase the risk of having excessive iodine levels and adversely affecting thyroid function. Monitor thyroid function.
Antithyroid Drugs
Due to its iodine content, Fucus vesiculosus might alter the effects of antithyroid drugs.
Fucus vesiculosus contains high concentrations of iodine. Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking Fucus vesiculosus while using antithyroid drugs could alter the effects of the antithyroid drugs.
Lithium
Concomitant use of Fucus vesiculosus and lithium has resulted in hyperthyroidism.
There is a case of hyperthyroidism occurring in a patient taking Fucus vesiculosus and lithium. Monitor thyroid hormones closely in patients taking lithium and Fucus vesiculosus concomitantly.
Thyroid Hormone
Due to its iodine content, Fucus vesiculosus might alter the effects of thyroid hormone.
Fucus vesiculosus contains high concentrations of iodine. Iodine in high doses has been reported to cause both hyperthyroidism and hypothyroidism, depending on the individual's past medical history. Taking Fucus vesiculosus while using thyroid hormone could alter the effects of thyroid hormone.
Anticoagulant/Antiplatelet Drugs
Theoretically, taking Fucus vesiculosus with antiplatelet or anticoagulant drugs might increase the risk of bruising and bleeding.
In vitro evidence suggests that a constituent of Fucus vesiculosus, known as fucoidan, has anticoagulant effects. However, in clinical research, fucoidan does not seem to have significant anticoagulant activity when taken orally, possibly due to poor absorption.
Cytochrome P450 2C8 (Cyp2C8) Substrates
Theoretically, concomitant use of Fucus vesiculosus with CYP2C8 substrates might increase the risk for adverse effects.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, inhibits CYP2C8. This interaction has not been reported in humans.
Cytochrome P450 2C9 (Cyp2C9) Substrates
Theoretically, concomitant use of Fucus vesiculosus with CYP2C9 substrates might increase the risk for adverse effects.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, inhibits CYP2C9. This interaction has not been reported in humans.
Cytochrome P450 2D6 (Cyp2D6) Substrates
Theoretically, concomitant use of Fucus vesiculosus with CYP2D6 substrates might alter the effects of these substrates.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, both inhibits and induces CYP2D6. This interaction has not been reported in humans.
Cytochrome P450 3A4 (Cyp3A4) Substrates
Theoretically, concomitant use of Fucus vesiculosus with CYP3A4 substrates might increase the risk for adverse effects.
In vitro research shows that fucoidan, a constituent of Fucus vesiculosus, inhibits CYP3A4. This interaction has not been reported in humans.
Brand information
Manufacturer and brand details for Bladderwrack Thallus, from the product label.
Nature's Answer
See all Nature's Answer products- Name
- Nature's Answer
- Street Address
- 85 Commerce Drive
- City
- Hauppauge
- State
- NY
- ZipCode
- 11788
- Phone Number
- (800) 439-2324
- Web Address
- www.naturesanswer.com
Bladderwrack Thallus by Nature's Answer: Common Questions
Does Bladderwrack Thallus by Nature's Answer interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Is this safe to take during pregnancy?
Can I take this while breastfeeding?
What does iodine actually do?
What side effects might I notice?
Can high doses cause acne?
Will this help with thyroid disease I already have?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Bladderwrack Thallus is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Bladderwrack Thallus’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Fucus Vesiculosus
Interacts with 891 drugsFucus vesiculosus (bladderwrack) is a brown seaweed rich in iodine that has been used traditionally for thyroid concerns, weight, and skin. There is little solid human evidence to support mo...
Read the full Fucus Vesiculosus monograph → Herb & supplement monographIodine
Interacts with 7 drugsIodine 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 & How We Checked
Bladderwrack Thallus'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 41 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.
Iodine 26 references
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
- Goodman GA, Rall TW, Nies AS, Taylor P. The Pharmacological Basis of Therapeutics, 9th ed.
- Ghent WR, Eskin BA, Low DA, Hill LP. Iodine replacement in fibrocystic disease of the breast. Can J Surg 1993;36:453-60.
- Potassium iodide for nuclear exposure. Pharmacist's Letter/Prescriber's Letter 2001;17(12):171214.
- 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.
- 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
- 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
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