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Dietary supplement

Klamath Lake Blue Green Algae 500 mg Ingredients & Drug Interactions

by Puritan's Pride Premium

Klamath Lake Blue Green Algae 500 mg label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Klamath Lake Blue Green Algae 500 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: Moderate

Klamath Lake Blue Green Algae 500 mg is a dietary supplement by Puritan's Pride Premium 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 Klamath Lake Blue Green Algae. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium

Ask about any prescription or over-the-counter medication and we check it for interactions with Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium

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: Klamath Lake Blue Green Algae, 500 mg per capsule. Blue-green algae are nutrient-dense microorganisms harvested from freshwater lakes.

The capsule itself is filled with gelatin, silica, and magnesium stearate — standard inactive ingredients that help hold the capsule together and make it easier to swallow.

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?
  • The label markets general wellness (“General nutrition and antioxidant support”), not a specific health condition, so there is no single claim to grade against clinical-evidence data.
  • 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).

The evidence for blue-green algae is mixed and often limited. It's rated possibly effective for high blood pressure (hypertension).

For acne, hay fever (allergic rhinitis), iron deficiency anemia, and arsenic poisoning, the research we hold is insufficient — we can't say whether it works for those uses. If you're considering this product for a specific health concern, talk with your pharmacist or doctor about whether the evidence supports it for your situation.

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.

Blue-green algae are generally well tolerated when taken by mouth, but quality and safety are real concerns. Some products can be contaminated with toxins or heavy metals, which is why the safety data advises caution.

The most common side effects are mild digestive issues — abdominal cramps, bloating, diarrhea, nausea, vomiting, flatulence, headache, dizziness, and fatigue. Allergic reactions are rare but possible, including rash, itching, and in one reported case, a serious reaction (anaphylaxis) several hours after taking the supplement.

A small number of people taking high doses reported mild gum bleeding or bruising.

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.

Before taking Klamath Lake Blue Green Algae, double-check your medications against these categories: blood thinners and antiplatelet drugs (Moderate severity), immunosuppressants (Moderate), and antidiabetes medications (Moderate). No interactions are documented for any other drug types in our data.

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.

This product might be worth considering if you're interested in its possible blood-pressure benefit and you don't take blood thinners, immune-suppressing drugs, or diabetes medications. Quality is a real concern — contamination with toxins or heavy metals is possible.

Before you start, run your medications through the checker on this page and have a conversation with your pharmacist.

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 24, 2023.

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 Klamath Lake Blue Green Algae 500 mg, straight from the product label.

Brand Puritan's Pride Premium
Barcode (UPC) 074312125423
Net contents 120 Rapid Release Capsule(s)
Market status On market
Date entered into DSLD May 24, 2023
DSLD ID 286185
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses Nutrient, All Other
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar 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 Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
120
UPC/BARCODE
074312125423
IngredientAmount% DV
Klamath Lake Blue Green Algae500 mg--

Other ingredients: Gelatin, Silica, Magnesium Stearate

Tap any ingredient to jump to its full detail below.

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

Shop online www.puritan.com

Puritan's Pride supplements are produced from the finest raw materials under stringent quality standards. State-of-the-art manufacturing and packaging facilities ensure you the highest quality nutritional supplements money can buy. When it comes to your health...choose the best.

To reorder item # 2542 www.puritan.com 1-800-645-1030

Formula

Aphanizomenon flos-aquae 500 mg Naturally occurring chlorophyll, amino acids & phytonutrients

FDA Statement of Identity

Dietary Supplements

Suggested/Recommended/Usage/Directions

Directions: For adults, start with one (1) capsule daily, and build up to two (2) to six (6) capsules per day. Should be taken with 8 ounces of water in the morning.

Formulation

No artificial color, flavor or sweetener, no preservatives, no sugar, no starch, no milk, no lactose, no soy, no gluten, no wheat, no yeast, no fish. Sodium free.

Precautions

Warning: If you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use.

Discontinue use and consult your doctor if any adverse reactions occur.

Keep out of reach of children.

Do not use if seal under cap is broken or missing.

Storage

Store at room temperature.

Brand IP Statement(s)

Copyright 2013 puritan's Pride, Inc.

Seals/Symbols

QA Quality Assured

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

See for yourself

Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium label

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

Klamath Lake Blue Green Algae 500 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 Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container120 Amounts shown are per serving.

Klamath Lake Blue Green Algae

Interacts with
327 drugs
500 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...

Klamath Lake Blue Green Algae monograph & interactions

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

Interaction report

Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium Drug Interactions

Want to check YOUR meds against Klamath Lake Blue Green Algae 500 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
327Drugs
327 Moderate

Ingredients driving the most interactions

Klamath Lake Blue Green Algae 327

Individual Drug Interactions

The ingredients in Klamath Lake Blue Green Algae 500 mg interact with 327 drugs. Click any drug to see the details.

1 of the 1 ingredient in Klamath Lake Blue Green Algae 500 mg interact with drugs. Each result below shows which ingredient is responsible. Klamath Lake Blue Green Algae

Each ingredient & the kinds of drugs it affects

For each ingredient in Klamath Lake Blue Green Algae 500 mg 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.

Klamath Lake Blue Green Algae3 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
Klamath Lake Blue Green Algae full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Klamath Lake Blue Green Algae 500 mg, from the product label.

Puritan's Pride Premium

See all Puritan's Pride Premium products
Name
Puritan's Pride, Inc.
City
Holbrook
State
NY
ZipCode
11741
Phone Number
1-800-645-1030
Web Address
www.puritan.com
Pharmacist Counseling Corner

Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium: Common Questions

Does Klamath Lake Blue Green Algae 500 mg by Puritan's Pride Premium interact with any medications?
Yes. Based on its ingredients, Klamath Lake Blue Green Algae 500 mg 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?
Klamath Lake Blue Green Algae 500 mg 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.
Does this actually work for anything?
The evidence shows it's possibly effective for high blood pressure. For other common uses like acne, hay fever, or anemia, the research we have isn't strong enough to say whether it works. Talk with your pharmacist about whether it makes sense for what you're trying to address.
What are the most common side effects?
Digestive upset is most likely — bloating, gas, diarrhea, nausea, and cramping. You might also feel dizzy, tired, or get a headache. These tend to be mild, but start low if you're new to it and see how your body reacts.
Can I take this if I'm pregnant or breastfeeding?
The data we hold doesn't include safety information for pregnancy or breastfeeding. There isn't enough information to know either way, so talk with your doctor or pharmacist before using it — they can give you personalized guidance.
Why does the safety warning mention contamination?
Blue-green algae are grown in freshwater, and quality varies a lot between products. Some batches can pick up toxins or heavy metals from the water. That's why the safety data recommends caution and notes the contamination risk.
Is this safe to use long-term?
We don't have long-term safety data on file. A small number of people taking high-dose spirulina reported mild bleeding or bruising over 2 weeks, which is rare. For ongoing use, talk with your pharmacist about monitoring and whether this product is right for you.

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

Not sure if Klamath Lake Blue Green Algae 500 mg is safe with your meds?

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Ask a pharmacist

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.

Klamath Lake Blue Green Algae 500 mg label
Go deeper

The Full Monographs Behind Klamath Lake Blue Green Algae 500 mg’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

Klamath Lake Blue Green Algae 500 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 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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