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Dietary supplement

Pure Spirulina (Algae Pratensis) Powder Ingredients & Drug Interactions

by Hard Rhino

Pure Spirulina (Algae Pratensis) Powder label
See full label image
Powder Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Pure Spirulina (Algae Pratensis) Powder 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: Moderate

Pure Spirulina (Algae Pratensis) Powder is a dietary supplement by Hard Rhino with 1 active ingredient. Its ingredients are commonly taken for general nutrition and energy, antioxidant support, cholesterol and metabolic health.Based on those ingredients, 327 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Spirulina. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Pure Spirulina (Algae Pratensis) Powder by Hard Rhino

Ask about any prescription or over-the-counter medication and we check it for interactions with Pure Spirulina (Algae Pratensis) Powder by Hard Rhino — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Pure Spirulina (Algae Pratensis) Powder by Hard Rhino

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: spirulina (blue-green algae). It's a single-ingredient powder with no other active components listed.

Does it work?

Moderate 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 Blue-green Algae's overall clinical evidence instead.

Moderate

Some clinical evidence supports Blue-green Algae 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 ingredient's overall clinical evidence instead.
  • On file: Hypertension — rated "Possibly Effective" (Natural Medicines).

Spirulina is possibly effective for high blood pressure (hypertension). For acne, hay fever (allergic rhinitis), iron deficiency anemia, and arsenic poisoning, the evidence isn't strong enough to rate it either way—we don't have enough reliable data to say whether it works for those uses.

The evidence, ingredient by ingredient Blue-green Algae

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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Spirulina is generally well tolerated when taken orally. Common side effects include stomach cramps, bloating, diarrhea, dizziness, fatigue, gas, headache, nausea, and vomiting.

Allergic reactions are uncommon but possible—rashes and itching have been reported, and in rare cases, a serious reaction (anaphylaxis) has occurred. A few cases of mild gum bleeding and bruising were reported in people taking 2.3 grams daily for two weeks.

The biggest safety concern is quality and contamination. Some spirulina products can contain toxins or heavy metals, so sourcing matters.

There isn't enough safety data for pregnancy or breastfeeding—talk with your pharmacist or doctor for personalized advice if you're pregnant, nursing, or planning to be.

Side effects, ingredient by ingredient Blue-green Algae

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Blue-green Algae.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 327 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 before starting if you take blood thinners (anticoagulants) or antiplatelet drugs like warfarin or aspirin, immunosuppressants, or diabetes medications. Spirulina may increase bleeding risk with blood thinners, reduce how well immunosuppressants work, and lower your blood sugar further if you're on diabetes drugs.

Check your own medication Run your meds through the checker above

The bottom line

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

Spirulina may help with high blood pressure, but it's not proven for most other uses people try it for. If you take blood thinners, immunosuppressants, or diabetes medications, you need to check with your pharmacist first—this product can interfere with them.

Buy from a reputable brand and watch for stomach upset.

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 Jun 25, 2014.

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 Pure Spirulina (Algae Pratensis) Powder, straight from the product label.

Brand Hard Rhino
Net contents 500 Gram(s); 1.1 lb
Market status On market
Date entered into DSLD Jun 25, 2014
DSLD ID 34539
Product type Non-nutrient/non-botanical
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Pure Spirulina (Algae Pratensis) Powder by Hard Rhino, 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:
3000 mg
Maximum serving Sizes:
10000 mg
Servings per container
166
IngredientAmount% DV
Spirulina3000 mg--

Other ingredients: Spirulina (Algae Pratensis) Powder

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.
Storage

Storage: Store in a cool & dry place. Keep away from direct sunlight and heat.

Storage: Store in a cool & dry place. Keep away from strong light & heat.

Precautions

WARNING: A micro scale is required for accurate measurements.

Do not take this or any other supplement if you are pregnant or nursing, have high blood pressure or taking other prescription drugs.

WARNING: A scale is required for accurate measurements.

Keep away from children.

Do not take this or any other supplement if you are pregnant or nursing.

Do not take if you have high blood pressure or any medical complications.

General Statements

Always consult with a physician before taking any new dietary supplement.

Quality Healthcare Worldwide

Always consult with your physician before taking any new dietary supplements. Expiration date on back of pouch.

USP-FCC

This is a NON-GMO ingredient produced with organic material.

Formulation

No added fillers No flow agents No driers No other ingredients

Allergens: This product contains NO Soy, Milk & Byproducts, Eggs, Fish, Shellfish, Wheat, Gluten, Tree Nuts, or Sesame Seeds.

Suggested/Recommended/Usage/Directions

Suggested Use: Dosages for Spirulina is commonly between 3,000 mg and 10,000 mg (about 1 to 2 teaspoons) daily. As with all of our powders, a micro scale is strongly recommended for proper dosage.

Suggested Use: As a dietary supplement take 3000mg daily, or as needed, preferably with juice or in shakes.

FDA Disclaimer Statement

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

FDA Statement of Identity

DIETARY SUPPLEMENT

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

See for yourself

Pure Spirulina (Algae Pratensis) Powder by Hard Rhino label

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

Pure Spirulina (Algae Pratensis) Powder 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 Pure Spirulina (Algae Pratensis) Powder by Hard Rhino

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size3000 mg Dosage formPowder Servings per container166 Amounts shown are per serving.

Spirulina

Interacts with
327 drugs
3000 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 monograph & interactions

Other (inactive) ingredients: Spirulina (Algae Pratensis) Powder. These complete the product’s ingredient list but are not active constituents.

Interaction report

Pure Spirulina (Algae Pratensis) Powder by Hard Rhino Drug Interactions

Want to check YOUR meds against Pure Spirulina (Algae Pratensis) Powder?

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
327Drugs
327 Moderate

Ingredients driving the most interactions

Spirulina 327

Individual Drug Interactions

The ingredients in Pure Spirulina (Algae Pratensis) Powder interact with 327 drugs. Click any drug to see the details.

1 of the 1 ingredient in Pure Spirulina (Algae Pratensis) Powder interact with drugs. Each result below shows which ingredient is responsible. Spirulina

Each ingredient & the kinds of drugs it affects

For each ingredient in Pure Spirulina (Algae Pratensis) Powder 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.

Spirulina3 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 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Pure Spirulina (Algae Pratensis) Powder, from the product label.

Hard Rhino

See all Hard Rhino products
Name
GUARDIAN Biosciences
City
Phoenix
State
Arizona
Pharmacist Counseling Corner

Pure Spirulina (Algae Pratensis) Powder by Hard Rhino: Common Questions

Does Pure Spirulina (Algae Pratensis) Powder by Hard Rhino interact with any medications?
Yes. Based on its ingredients, Pure Spirulina (Algae Pratensis) Powder has a known interaction with 327 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Pure Spirulina (Algae Pratensis) Powder contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 spirulina if I'm pregnant or breastfeeding?
There isn't enough safety data to know either way. Talk with your pharmacist or doctor about whether it's right for you—it's a personal medical decision that depends on your situation.
What are the most common side effects?
Stomach cramps, bloating, gas, diarrhea, nausea, headache, dizziness, and fatigue. Most people tolerate it well, but if these bother you, mention it to your pharmacist.
Can spirulina help my high blood pressure?
Spirulina is possibly effective for high blood pressure based on available evidence. It's not a replacement for your blood pressure medication, but it may be worth discussing with your doctor as part of your overall plan.
Does it work for acne or hay fever?
We don't have enough reliable evidence to say whether spirulina helps with either one. The data just isn't strong enough to rate it for those uses.
Is there a concern about quality?
Yes. Some spirulina products can be contaminated with toxins or heavy metals, so sourcing and brand reputation matter. Buy from a company you trust.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Pure Spirulina (Algae Pratensis) Powder is safe with your meds?

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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.

Pure Spirulina (Algae Pratensis) Powder label
Go deeper

The Full Monographs Behind Pure Spirulina (Algae Pratensis) Powder’s Ingredients

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

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 →
Sources

Sources & How We Checked

Pure Spirulina (Algae Pratensis) Powder'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 22 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.

Blue-green Algae 22 references
  1. Jensen GS, Ginsberg DJ, Huerta P, et al. Consumption of Aphanizomenon flos-aquae has rapid effects on the circulation and function of immune cells in humans. A novel approach to nutritional mobilization of the immune system. JANA 2000;2:50-6.
  2. Iwasa M, Yamamoto M, Tanaka Y, et al. Spirulina-associated hepatotoxicity. Am J Gastroenterol 2002;97:3212-13. PubMed
  3. Hayashi O, Katoh T, Okuwaki Y. Enhancement of antibody production in mice by dietary Spirulina platensis. J Nutr Sci Vitaminol (Tokyo) 1994;40:431-41.. PubMed
  4. Vitale S, Miller NR, Mejico LJ, et al. A randomized, placebo-controlled, crossover clinical trial of super blue-green algae in patients with essential blepharospasm or Meige syndrome. Am J Ophthalmol 2004;138:18-32. PubMed
  5. Mani UV, Desai S, Iyer U. Studies on the long-term effect of spirulina supplementation on serum lipid profile and glycated proteins in NIDDM patients. J Nutraceut 2000;2(3):25-32. DOI
  6. Chiu HF, Yang SP, Kuo YL, et al. Mechanisms involved in the antiplatelet effect of C-phycocyanin. Br J Nutr 2006;95:435-40. PubMed
  7. Hsiao G, Chou PH, Shen MY, et al. C-phycocyanin, a very potent and novel platelet aggregation inhibitor from Spirulina platensis. J Agric Food Chem 2005;53:7734-40.
  8. Katz M, Levine AA, Kol-Degani H, Kav-Venaki L. A compound herbal preparation (CHP) in the treatment of children with ADHD: a randomized controlled trial. J Atten Disord 2010;14:281-91. PubMed
  9. Madhyastha, H. K., Radha, K. S., Sugiki, M., Omura, S., and Maruyama, M. Purification of c-phycocyanin from Spirulina fusiformis and its effect on the induction of urokinase-type plasminogen activator from calf pulmonary endothelial cells. Phytomedicine PubMed
  10. Mazokopakis, E. E., Karefilakis, C. M., Tsartsalis, A. N., Milkas, A. N., and Ganotakis, E. S. Acute rhabdomyolysis caused by Spirulina (Arthrospira platensis). Phytomedicine. 2008;15(6-7):525-527. PubMed
  11. Halidou, Doudou M., Degbey, H., Daouda, H., Leveque, A., Donnen, P., Hennart, P., and Dramaix-Wilmet, M. [The effect of spiruline during nutritional rehabilitation: systematic review]. Rev.Epidemiol.Sante Publique 2008;56(6):425-431.
  12. Konno, T., Umeda, Y., Umeda, M., Kawachi, I., Oyake, M., and Fujita, N. [A case of inflammatory myopathy with widely skin rash following use of supplements containing Spirulina]. Rinsho Shinkeigaku 2011;51(5):330-333. PubMed
  13. Le TM, Knulst AC, Röckmann H. Anaphylaxis to Spirulina confirmed by skin prick test with ingredients of Spirulina tablets. Food Chem Toxicol 2014;74:309-10. PubMed
  14. Rzymski P, Niedzielski P, Kaczmarek N, Jurczak T, Klimaszyk P. The multidisciplinary approach to safety and toxicity assessment of microalgae-based food supplements following clinical cases of poisoning. Harmful Algae 2015;46:34-42. DOI
  15. Petrus M, Culerrier R, Campistron M, et al. First case report of anaphylaxis to spirulin: identification of phycocyanin as responsible allergen. Allergy 2010;65(7):924-5. PubMed
  16. Marles RJ, Barrett ML, Barnes J, et al. United States Pharmacopeia safety evaluation of spirulina. Crit Rev Food Sci Nutr 2011;51(7):593-604. PubMed
  17. Majdoub H, Ben Mansour M, Chaubet F, et al. Anticoagulant activity of a sulfated polysaccharide from the green alga Arthrospira platensis. Biochim Biophys Acta 2009;1790(10):1377-81. PubMed
  18. Cha BG, Kwak HW, Park AR, et al. Structural characteristics and biological performance of silk fibroin nanofiber containing microalgae spirulina extract. Biopolymers 2014;101(4):307-18. PubMed
  19. Jensen GS, Drapeau C, Lenninger M, Benson KF. Clinical safety of a high dose of phycocyanin-enriched aqueous extract from Arthrospira (Spirulina) platensis: results from a randomized, double-Blind, placebo-controlled study with a focus on anticoagulant ac
  20. Hamedifard Z, Milajerdi A, Reiner Z, Taghizadeh M, Kolahdooz F, Asemi Z. The effects of spirulina on glycemic control and serum lipoproteins in patients with metabolic syndrome and related disorders: A systematic review and meta-analysis of randomized con
  21. Moradi S, Zobeiri M, Feizi A, Clark CCT, Entezari MH. The effects of spirulina (Arthrospira platensis) supplementation on anthropometric indices, blood pressure, sleep quality, mental health, fatigue status and quality of life in patients with ulcerative
  22. Ghanbari F, Amerizadeh A, Behshood P, Moradi S, Asgary S. Effect of microalgae arthrospira on biomarkers of glycemic control and glucose metabolism: a systematic Review and meta-analysis. Curr Probl Cardiol 2022;47(10):100942. PubMed

See these in context on the Blue-green Algae monograph →

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

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