Icelandic Kelp Ingredients & Drug Interactions
by NaturesPlus
What is this page for?
First and foremost: checking Icelandic Kelp 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
Icelandic Kelp is a dietary supplement by NaturesPlus with 2 active ingredients. Its ingredients are commonly taken for preventing iodine deficiency, supporting thyroid hormone production, general energy and metabolism support.Based on those ingredients, 7 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Iodine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Icelandic Kelp by NaturesPlus
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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 Icelandic Kelp by NaturesPlus
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
Icelandic Kelp by NaturesPlus is a 2-ingredient product centered on iodine, a mineral your thyroid needs to work properly. Kelp is a seaweed that's a natural source of iodine.
The remaining ingredients are inactive fillers (cellulose, silica, and other binding agents) that give the tablet its form.
Does it work?
Strong evidence
Iodine in this product is likely effective for protecting against radiation exposure and treating iodine deficiency. It's possibly effective for mouth sores (oral mucositis) and gum disease (periodontitis), though the evidence is less established.
We have no effectiveness data for the kelp ingredient itself.
How safe is it?
Well-documented data
Iodine is well tolerated in normal dietary amounts, but high doses can trigger thyroid problems like goiter (enlarged thyroid), low thyroid function (hypothyroidism), or overactive thyroid (hyperthyroidism). Common side effects at high intake include nausea, diarrhea, headache, and a metallic taste.
Rare but serious allergic reactions — such as swelling of the lips and throat (angioedema) — are possible if you're hypersensitive to iodine. In pregnancy, some iodine is important, but your doctor should set the dose; high amounts can affect your baby's thyroid.
During breastfeeding, excess iodine can pass into breast milk, so follow your doctor's guidance on how much to take.
Meds to double-check
Moderate interaction found
Check your medications if you take lithium, antithyroid drugs, or amiodarone (Cordarone) — these have documented Moderate interactions with the iodine in this product. Use the medication checker below to verify your exact drugs before adding this supplement.
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 product is useful if you're iodine-deficient or need radiation protection, but it's not a casual multivitamin — iodine dose matters. If you take lithium, antithyroid drugs, or amiodarone, check with your pharmacist first.
Anyone with a history of thyroid problems or iodine sensitivity should talk to their doctor before starting.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 1 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 21, 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
General information
Key facts about Icelandic Kelp, straight from the product label.
| Brand | NaturesPlus |
|---|---|
| Barcode (UPC) | 097467039506 |
| Net contents | 300 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Dec 21, 2024 |
| DSLD ID | 319187 |
| Product type | Botanical With Nutrients |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Dairy 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 Icelandic Kelp by NaturesPlus, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Iodine | 150 mcg | 100% |
| Icelandic Kelp | 150 mg | -- |
Other ingredients: Microcrystalline Cellulose, Dicalcium Phosphate, Stearic Acid, Silica, Magnesium Stearate, Cellulose, Alfalfa
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.
Formulation
Free from synthetic: Colors, preservatives. Free from milk, egg, tree nuts, peanut, wheat, soy and sesame. Gluten-free
Thyroid support Antioxidant support
Storage
Keep tightly closed in a cool, dry place.
Precautions
Keep out of reach of children.
Please see new allergen information.
Contains fish, crustacean shellfish.
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.
Formula
Featuring trace mineral-rich geothermal Icelandic kelp! Naturally occurring iodine
FDA Statement of Identity
Dietary Supplement
Suggested/Recommended/Usage/Directions
Directions: One tablet daily.
Brand IP Statement(s)
Copyright Natural Organics
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Icelandic Kelp by NaturesPlus 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 Icelandic Kelp by NaturesPlus
These are the 2 active ingredients this product is made of. Select any to open its full monograph.
Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container300 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.
Iodine
Interacts with7 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...
Iodine monograph & interactionsIcelandic Kelp
Other (inactive) ingredients: Microcrystalline Cellulose, Dicalcium Phosphate, Stearic Acid, Silica, Magnesium Stearate, Cellulose, Alfalfa. These complete the product’s ingredient list but are not active constituents.
Icelandic Kelp by NaturesPlus Drug Interactions
HelloPharmacist Interaction Report
NaturesPlus Icelandic Kelp contains iodine, which has documented interactions with seven individual medications.
The most serious concern is with lithium (used for mood disorders), where combining them might add up to reduce thyroid function — your doctor may need to monitor your thyroid if you take both. Iodine can also interfere with antithyroid drugs (medications that lower thyroid hormone) and amiodarone (Cordarone), a heart rhythm medication that's already high in iodine itself; using them together risks excessive iodine levels and thyroid problems.
Altogether, these interactions span 7 individual medications. The kelp ingredient itself hasn't been checked for interactions — we hold no data for it.
Before you start this product, run your exact medications through the checker on this page.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Icelandic Kelp?
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 Icelandic Kelp interact with 7 drugs. Click any drug to see the details.
1 of the 2 ingredients in Icelandic Kelp interact with drugs. Each result below shows which ingredient is responsible. Iodine
AmiodaroneCordarone, Pacerone
How Amiodarone interacts with Icelandic Kelp — through 1 ingredient. Tap an ingredient for the detail:
IodineAmiodarone (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 Icelandic Kelp — through 1 ingredient. Tap an ingredient for the detail:
IodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Carbimazole interactionLithium Carbonate (prescription Drug)Eskalith, Lithium Carbonate
How Lithium Carbonate (prescription Drug) interacts with Icelandic Kelp — through 1 ingredient. 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) interactionMethenamine MandelateMandelamine, Methimazole
How Methenamine Mandelate interacts with Icelandic Kelp — through 1 ingredient. 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 interactionMethimazoleTapazole
How Methimazole interacts with Icelandic Kelp — through 1 ingredient. Tap an ingredient for the detail:
IodineAntithyroid Drugs Moderate
Interaction Summary
Iodine might alter the effects of antithyroid drugs.
Read the full Iodine + Methimazole interactionPotassium Iodide (prescription Drug)Thyro-Block
How Potassium Iodide (prescription Drug) interacts with Icelandic Kelp — through 1 ingredient. 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) interactionPropylthiouracil, PtuPropylthiouracil
How Propylthiouracil, Ptu interacts with Icelandic Kelp — through 1 ingredient. 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 interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Icelandic Kelp 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.
Iodine
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.
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.
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.
Brand information
Manufacturer and brand details for Icelandic Kelp, from the product label.
NaturesPlus
See all NaturesPlus products- Name
- Natural Organics, Inc. makers of NaturesPlus
- Street Address
- 9500 New Horizons Blvd.
- City
- Amityville
- State
- New York
- ZipCode
- 11701
- Web Address
- natureplus.com
Icelandic Kelp by NaturesPlus: Common Questions
Does Icelandic Kelp by NaturesPlus interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Is this safe to take if I'm pregnant?
Can I take this while breastfeeding?
What does iodine actually do?
Are there any side effects at normal doses?
What's the difference between 'iodine allergy' and actual iodine hypersensitivity?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Icelandic Kelp 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 Icelandic Kelp’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Icelandic Kelp'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 26 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
- Yarrington CD, Pearce EN. Dietary iodine in pregnancy and postpartum. Clin Obstet Gynecol 2011;54:459-70. PubMed
- 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
- 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
- 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
- Ohkuma, M. Molluscum contagiosum treated with iodine solution and salicylic acid plaster. Int J Dermatol. 1990;29(6):443-445. PubMed
- 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
- 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.
- 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
- 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
- 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
- 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.
- Iodine Hypersensitivity. Pharmacist's Letter/Prescriber's Letter 2011; 27(5):270504.
- 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
- 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
- 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
- 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
- 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
- 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
- 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
Parts of this content are provided by the Therapeutic Research Center, LLC.
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