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Dietary supplement

Organic Spirulina 2,000 mg Ingredients & Drug Interactions

by Dr. Mercola

Organic Spirulina 2,000 mg label
See full label image
Tablet Or Pill 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 Organic Spirulina 2,000 mg 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

Organic Spirulina 2,000 mg is a dietary supplement by Dr. Mercola with 4 active ingredients. Its ingredients are commonly taken for iron-deficiency anemia, low iron stores during pregnancy, fatigue from iron deficiency.Based on those ingredients, 910 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin A, Spirulina, Powder, Iron. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Organic Spirulina 2,000 mg by Dr. Mercola

Ask about any prescription or over-the-counter medication and we check it for interactions with Organic Spirulina 2,000 mg by Dr. Mercola — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Organic Spirulina 2,000 mg by Dr. Mercola

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 Aug 27, 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 5 of its 5 active ingredients.
  • “Spirulina, Powder” is listed as a grouped ingredient — the label gives one combined amount (2,000 mg) without saying how much of each component you get.

This tablet contains five active ingredients. Iron supports red blood cell production and is used to treat iron-deficiency anemia.

Spirulina is a blue-green algae powder that serves as the product's main base. Carotenoids are plant pigments with antioxidant properties.

Chlorophyll is the green pigment in plants, included for general wellness support. Vitamin A (from the carotenoids) supports vision, skin, and immune function.

The inactive ingredient is silicon dioxide, a drying and anti-caking agent.

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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Anemia of chronic disease — rated "Effective" (Iron) (Natural Medicines).
  • On file: Vitamin A deficiency — rated "Effective" (Vitamin A) (Natural Medicines).
  • On file: Iron deficiency anemia — rated "Effective" (Iron) (Natural Medicines).
  • On file: Pregnancy-related iron deficiency — rated "Effective" (Iron) (Natural Medicines).
  • On file: Aging skin — rated "Possibly Effective" (Vitamin A) (Natural Medicines).

Iron is effective for iron-deficiency anemia and anemia of chronic disease, and possibly effective for heart failure. Vitamin A is effective for vitamin A deficiency, and possibly effective for oral leukoplakia, aging skin, measles, ulcerative colitis, and bronchopulmonary dysplasia.

Chlorophyll's evidence for genital herpes, wound healing, shingles, nonmelanoma skin cancer, and pancreatitis is insufficient — we don't have enough reliable data to rate whether it works. We hold no effectiveness data for spirulina, carotenoids, or phycocyanin as they appear in this product.

The evidence, ingredient by ingredient Iron Blue-green Algae Chlorophyll Vitamin A

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Iron is generally well tolerated when used appropriately at recommended doses, though excess iron can be toxic and supplements should be used only when there is a real need. The most common side effects from iron are abdominal pain, constipation, diarrhea, nausea, and vomiting.

Rare serious effects include gastric ulcerations. Chlorophyll is generally well tolerated in short-term use, but high-quality safety data are limited.

The main side effect is photosensitization (sun sensitivity), and rare cases of pseudoporphyria (blistering) have been reported with oral use. Vitamin A at recommended doses is generally safe, but high doses are toxic because the body stores it; serious effects at very high doses include liver damage, headache, and in extreme cases coma or death.

Side effects, ingredient by ingredient Iron Blue-green Algae Chlorophyll Vitamin A

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?
  • 3 of the 3 matched ingredients can interact with medications — Chlorophyll, Iron, Vitamin A.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; Parkinson's medications.
  • For scale: 661 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 doctor or pharmacist before taking this if you use retinoids (Major severity), or quinolone or tetracycline antibiotics, bisphosphonates, methyldopa, levothyroxine, mycophenolate mofetil, penicillamine, warfarin, levodopa, methotrexate, or photosensitizing drugs (Moderate severity). Iron and vitamin A can reduce the absorption or effectiveness of many of these, and high-dose vitamin A can increase bleeding risk with warfarin and pseudotumor cerebri risk with tetracyclines.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

This product is useful if you have iron-deficiency anemia or need vitamin A supplementation. If you take any retinoid (acne or anti-aging prescription), any antibiotic, a blood thinner like warfarin, thyroid medication, a bisphosphonate for bone health, or drugs for Parkinson's disease, autoimmune conditions, or heavy-metal poisoning, talk with your doctor or pharmacist before starting — the iron and other ingredients may reduce how well your medications work.

Those planning pregnancy should confirm iron dosing and avoid high-dose vitamin A with their prenatal care provider.

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

Assessment coverage: 3 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 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 Organic Spirulina 2,000 mg, straight from the product label.

Brand Dr. Mercola
Barcode (UPC) 810487034340
Net contents 120 Tablet(s)
Market status On market
Date entered into DSLD Mar 22, 2024
DSLD ID 308857
Product type Other Combinations
Supplement form Tablet Or Pill
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Organic
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 Organic Spirulina 2,000 mg by Dr. Mercola, 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:
4 Tablet(s)
Maximum serving Sizes:
4 Tablet(s)
Servings per container
30
UPC/BARCODE
810487034340
IngredientAmount% DV
Calories10 Calorie(s)--
Iron1 mg6%
Protein1 Gram(s)2%
Spirulina, Powder2000 mg--
Carotenoids7.2 mg--
Chlorophyll22 mg--
Phycocyanin280 mg--
Vitamin A230 mcg26%

Other ingredients: 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.
Suggested/Recommended/Usage/Directions

Suggested use: Adults, as a dietary supplement, take four (4) tablets daily.

Precautions

Warning: Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6. Keep this product out of reach of children. In case of accidental overdose, call a doctor or poison control center immediately.

Do not use if safety seal is broken.

If you are nursing, pregnant, taking medication or have a medical condition, consult your physician before taking this product.

Formula

Organic Spirulina 2,000 mg per serving

Seals/Symbols

USDA Organic

FDA Statement of Identity

Dietary Supplement

Formulation

Certified Organic by: QCS

Product of India

Brand IP Statement(s)

Dr. Mercola Providing quality products since 2001.

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

See for yourself

Organic Spirulina 2,000 mg by Dr. Mercola label

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

Organic Spirulina 2,000 mg 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 Organic Spirulina 2,000 mg by Dr. Mercola

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

Serving size4 Tablet(s) Dosage formTablet Or Pill 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.

Iron

Interacts with
80 drugs
1 mg per serving

Iron is an essential mineral your body needs to make hemoglobin and carry oxygen in the blood. Supplements are mainly useful for treating or preventin...

Iron monograph & interactions

Protein

1 Gram(s) per serving

Spirulina, Powder

Interacts with
327 drugs
2000 mg per serving

Blue-green algae are nutrient-rich aquatic microorganisms (such as spirulina and Klamath Lake algae) taken as a supplement for energy, nutrition, and...

Spirulina, Powder monograph & interactions

Vitamin A

Interacts with
387 drugs
230 mcg per serving Form: Beta-Carotene

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

Vitamin A monograph & interactions

Other (inactive) ingredients: Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Organic Spirulina 2,000 mg by Dr. Mercola Drug Interactions

Want to check YOUR meds against Organic Spirulina 2,000 mg?

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
910Drugs
9 Major 900 Moderate 1 Minor

Ingredients driving the most interactions

Vitamin A 387
Spirulina, Powder 327
Iron 80

Individual Drug Interactions

The ingredients in Organic Spirulina 2,000 mg interact with 910 drugs. Click any drug to see the details.

3 of the 4 ingredients in Organic Spirulina 2,000 mg interact with drugs. Each result below shows which ingredient is responsible. Vitamin A Spirulina, Powder Iron

Each ingredient & the kinds of drugs it affects

For each ingredient in Organic Spirulina 2,000 mg 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.

Vitamin A4 drug types · 387 drugs

Retinoids

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

Likelihood Probable Evidence D
Hepatotoxic Drugs

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

Likelihood Possible Evidence C
Tetracycline Antibiotics

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

Likelihood Possible Evidence D
Warfarin (Coumadin)

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

Likelihood Possible Evidence D
Vitamin A full monograph & interactions

Spirulina, Powder3 drug types · 327 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, spirulina blue-green algae might increase the risk of bleeding if used with other anticoagulant or antiplatelet drugs. However, this is unlikely.
Spirulina blue-green algae have shown antiplatelet and anticoagulant effects in vitro. However, one preliminary study in 24 patients receiving spirulina blue-green algae 2.3 grams daily for 2 weeks showed no effect on platelet activation or measures of clotting time.

Likelihood Unlikely Evidence D
Antidiabetes Drugs

Theoretically, taking blue-green algae with antidiabetes drugs might increase the risk of hypoglycemia.
Human research shows that spirulina blue-green algae can have hypoglycemic effects in patients with diabetes, at least some of whom were using antidiabetes drugs. However, blue-green algae does not seem to improve glycated hemoglobin (HbA1c) levels in patients with diabetes. A meta-analysis of animal studies also suggests that spirulina blue-green algae have hypoglycemic effects.

Likelihood Possible Evidence B
Immunosuppressants

Theoretically, concurrent use of blue-green algae might interfere with immunosuppressive therapy.
Blue-green algae have been shown to stimulate the immune system.

Likelihood Possible Evidence D
Spirulina, Powder full monograph & interactions

Iron13 drug types · 80 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Iron might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and iron can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, iron containing products.

Likelihood Probable Evidence D
Bisphosphonates

Iron reduces the absorption of bisphosphonates.
Advise patients that doses of bisphosphonates should be separated by at least two hours from doses of all other medications, including supplements such as iron. Divalent cations, including iron, can decrease absorption of bisphosphonates by forming insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence D
Denosumab (Prolia, Others)

Administration of intravenous iron within one month of denosumab administration might increase the risk of severe hypophosphatemia and hypocalcemia.
A case of severe hypocalcemia (albumin corrected calcium 6.88 mg/dL, ionized calcium 3.68 mg/dL) and hypophosphatemia (<0.5 mg/dL) with respiratory acidosis, QT interval prolongation, and nonsustained ventricular tachycardia was reported in a 76-year-old male who had received an iron polymaltose infusion within 2 weeks of a subcutaneous injection of denosumab. Serum parathyroid hormone was also elevated (348 pg/mL). Subsequent iron infusions with iron polymaltose and ferric carboxymaltose were followed by transient hypophosphatemia, but without hypocalcemia. Additionally, a literature review describes 6 additional cases of hypophosphatemia and hypocalcemia in patients 52-92 years of age who had been administered intravenous iron as either ferric carboxymaltose or iron polymaltose and subcutaneous denosumab within 1-4 weeks of each other.

Likelihood Possible Evidence D
Dolutegravir (Tivicay)

Iron might decrease dolutegravir levels by reducing its absorption.
Advise patients to take dolutegravir at least 2 hours before or 6 hours after taking iron. Pharmacokinetic research shows that iron can decrease the absorption of dolutegravir from the gastrointestinal tract through chelation. When taken under fasting conditions, a single dose of ferrous fumarate 324 mg orally along with dolutegravir 50 mg reduces overall exposure to dolutegravir by 54%.

Likelihood Probable Evidence B
Integrase Inhibitors

Theoretically, taking iron along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Iron is a divalent cation. There is concern that iron may decrease the absorption of integrase inhibitors from the gastrointestinal tract through chelation. One pharmacokinetic study shows that iron can decrease blood levels of the specific integrase inhibitor dolutegravir through chelation. Also, other pharmacokinetic research shows that other divalent cations such as calcium can decrease the absorption and levels of some integrase inhibitors through chelation.

Likelihood Possible Evidence D
Levodopa

Iron might decrease levodopa levels by reducing its absorption.
Advise patients to separate doses of levodopa and iron as much as possible. There is some evidence in healthy people that iron forms chelates with levodopa, reducing the amount of levodopa absorbed by around 50%. The clinical significance of this hasn't been determined.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Iron might decrease levothyroxine levels by reducing its absorption.
Advise patients to separate levothyroxine and iron doses by at least 2 hours. Iron can decrease the absorption and efficacy of levothyroxine by forming insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence B
Methyldopa (Aldomet)

Iron might decrease methyldopa levels by reducing its absorption.
Advise patients to separate methyldopa and iron doses by at least 2 hours. Iron can decrease the absorption of methyldopa from the gastrointestinal tract through chelation, resulting in increases in blood pressure.

Likelihood Probable Evidence B
Mycophenolate Mofetil (Cellcept)

Theoretically, iron might decrease mycophenolate mofetil levels by reducing its absorption.
Advise patients to take iron 4-6 hours before, or 2 hours after, mycophenolate mofetil. It has been suggested that a decrease of absorption is possible, probably by forming nonabsorbable chelates. However, mycophenolate pharmacokinetics are not affected by iron supplementation in available clinical research.

Likelihood Unlikely Evidence D
Penicillamine (Cuprimine, Depen)

Iron might decrease penicillamine levels by reducing its absorption.
Advise patients to separate penicillamine and iron doses by at least 2 hours. Oral iron supplements can reduce absorption of penicillamine by 30% to 70%, probably due to chelate formation. In people with Wilson's disease, this interaction has led to reduced efficacy of penicillamine.

Likelihood Probable Evidence D
Quinolone Antibiotics

Iron might decrease levels of quinolone antibiotics by reducing their absorption.
Advise patients to separate quinolone antibiotics and iron doses by at least 2 hours. Iron decreases the absorption of quinolones due to formation of insoluble complexes in the gastrointestinal tract.

Likelihood Probable Evidence D
Tetracycline Antibiotics

Iron might decrease levels of tetracycline antibiotics by reducing their absorption.
Advise patients to take iron at least 2 hours before or 4 hours after tetracycline antibiotics. Concomitant use can decrease absorption of tetracycline antibiotics from the gastrointestinal tract by 50% to 90%.

Likelihood Probable Evidence D
Chloramphenicol

Theoretically, taking chloramphenicol with iron might reduce the response to iron therapy in iron deficiency anemia.
Chloramphenicol interferes with erythrocyte maturation. However, since chloramphenicol isn't usually taken for prolonged periods, this isn't likely to be clinically significant.

Likelihood Unlikely Evidence D
Iron full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Organic Spirulina 2,000 mg, from the product label.

Dr. Mercola

See all Dr. Mercola products
Name
NHP
Street Address
125 SW 3rd Place
City
Cape Coral
State
FL
ZipCode
33991
Phone Number
(877) 985-2696
Pharmacist Counseling Corner

Organic Spirulina 2,000 mg by Dr. Mercola: Common Questions

Does Organic Spirulina 2,000 mg by Dr. Mercola interact with any medications?
Yes. Based on its ingredients, Organic Spirulina 2,000 mg has a known interaction with 910 medications, including 9 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Organic Spirulina 2,000 mg 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 spirulina while I'm pregnant or breastfeeding?
Iron is likely safe in pregnancy when doses are guided by your prenatal care provider and generally acceptable while breastfeeding at appropriate doses — check with your provider on both. Vitamin A at recommended amounts is needed in pregnancy, but high doses (especially as retinol) can cause birth defects, so avoid high-dose supplements. Chlorophyll safety data during pregnancy are insufficient — there isn't enough information to know either way, so talk with your doctor or pharmacist for personalized advice. We hold no pregnancy or breastfeeding data for the other ingredients.
What are the most common side effects from the iron in this product?
Abdominal pain, constipation, diarrhea, nausea, and vomiting are the most common side effects. Taking it with food can help reduce stomach upset, though it may reduce absorption slightly — ask your pharmacist about timing.
Is there vitamin A in this product, and is it safe to take with my retinoid acne cream?
Yes, vitamin A is present as part of the carotenoid content. Taking it with prescription retinoids (like tretinoin or isotretinoin) can produce dangerously high vitamin A levels with toxic effects. Do not combine them without checking with your doctor first.
I take levothyroxine for my thyroid. Can I take this spirulina?
The iron in this product can reduce how much levothyroxine your body absorbs, which may lower your thyroid hormone levels. Separate the two by at least 2 hours — take one in the morning and one in the afternoon or evening, and ask your pharmacist which order works best. Your doctor may need to check your thyroid levels after a few weeks.
Does this product contain anything that makes me sun-sensitive?
Yes, the chlorophyll can cause photosensitization — your skin may react more to sunlight. Wear sunscreen and protective clothing if you spend time in the sun, especially if you notice any redness or blistering on your skin.
How much vitamin A is in each tablet?
We don't have the exact amount per tablet in our data. Check the product label for the specific dose and make sure it's below 10,000 IU/day if you take warfarin or other medications affected by high vitamin A doses.

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.

Organic Spirulina 2,000 mg label
Go deeper

The Full Monographs Behind Organic Spirulina 2,000 mg’s Ingredients

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

Herb & supplement monograph

Iron

Interacts with 80 drugs

Iron is an essential mineral your body needs to make hemoglobin and carry oxygen in the blood. Supplements are mainly useful for treating or preventing iron deficiency and iron-deficiency an...

Read the full Iron monograph → Herb & supplement monograph

Blue-green Algae

Interacts with 327 drugs

Blue-green algae are nutrient-rich aquatic microorganisms (such as spirulina and Klamath Lake algae) taken as a supplement for energy, nutrition, and general wellness. Evidence for most heal...

Read the full Blue-green Algae monograph → Herb & supplement monograph

Chlorophyll

Interacts with 337 drugs

Chlorophyll is the green pigment found in plants and algae, and supplements often use a stable form called chlorophyllin. It is most studied for reducing body and fecal odor and as a topical...

Read the full Chlorophyll monograph → Herb & supplement monograph

Vitamin A

Interacts with 387 drugs

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

Read the full Vitamin A monograph →
Sources

Sources & How We Checked

Organic Spirulina 2,000 mg'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 130 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.

Iron 72 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Bruner AB, Joffe A, Duggan AK, et al. Randomized study of cognitive effects of iron supplementation in non- anaemic iron-deficient adolescent girls. Lancet 1996;348:992-6.
  3. Ullen H, Augustsson K, Gustavsson C, Steineck G. Supplementary iron intake and risk of cancer: reversed causality? Cancer Lett 1997;114:215-6.
  4. Reunanen A, Takkunen H, Knekt P, et al. Body iron stores, dietary iron intake and coronary heart disease mortality. J Intern Med 1995;238:223-30. PubMed
  5. Lund EK, Wharf SG, Fairweather-Tait SJ, Johnson IT. Oral ferrous sulfate supplements increase the free radical-generating capacity of feces from healthy volunteers. Am J Clin Nutr 1999;69:250-5.
  6. Rehman A, Collis CS, Yang M, et al. The effects of iron and vitamin C co-supplementation on oxidative damage to DNA in healthy volunteers. Biochem Biophys Res Comm 1998;246:293-8. PubMed
  7. Klipstein-Grobusch K, Grobbee DE, den Breeijen JH, et al. Dietary iron and risk of myocardial infarction in the Rotterdam Study. Am J Epidemiol 1999;149:421-8. PubMed
  8. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  9. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
  10. 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.
  11. Campbell N, Paddock V, Sundaram R. Alteration of methyldopa absorption, metabolism, and blood pressure control by ferrous sulfate and ferrous gluconate. Clin Pharmacol Ther 1988;43:381-6..
  12. Schumann K, Borch-Iohnsen B, Hentze MW, Marx JJ. Tolerable upper intakes for dietary iron set by the US Food and Nutrition Board (commentary). Am J Clin Nutr 2002;76:499-500. PubMed
  13. Tuomainen TP, Punnonen K, Nyyssonen K, Salonen JT. Association between body iron stores and the risk of acute myocardial infarction in men. Circulation 1998;97:1461-6.. PubMed
  14. Salonen JT, Nyyssonen K, Korpela H, et al. High stored iron levels are associated with excess risk of myocardial infarction in Eastern Finnish men. Circulation 1992;86:803-11.. PubMed
  15. Campbell NRC, Hasinoff B. Ferrous sulfate reduces levodopa bioavailability: Chelation as a possible mechanism. Clin Pharmacol Ther 1989;45:220-5.. PubMed
  16. Campbell NRC, Hasinoff BB, Stalts H, et al. Ferrous sulfate reduces thyroxine efficacy in patients with hypothyroidism. Ann Int Med 1992;117:1010-3.. PubMed
  17. Kiechl S, Willeit J, Egger G, et al. Body iron stores and the risk of carotid atherosclerosis: prospective results from the Bruneck study. Circulation 1997;96:3300-07. PubMed
  18. Comparison of oral iron supplements. Pharmacist's Letter / Prescriber's Letter 2008;24(8):240811.
  19. Tran T., Wax J. R., Philput C., Steinfeld J. D., Ingardia C. J. Intentional iron overdose in pregnancy--management and outcome. J Emerg Med 2000;18(2):225-228. PubMed
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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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