Drug & supplement interaction

Blue-green Algae + Glimepiride

Glimepiride brand name: Amaryl.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Blue-green Algae has a moderate interaction with Glimepiride. Theoretically, taking blue-green algae with antidiabetes drugs might increase the risk of hypoglycemia.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Blue-green Algae and Glimepiride

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ANTIDIABETES DRUGS

Why this applies to Glimepiride

Glimepiride falls under ANTIDIABETES DRUGS — the group Blue-green Algae interacts with.

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.
Severity Moderate Likelihood Possible Evidence B

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version: glimepiride already works hard to push your blood sugar down by getting your pancreas to release more insulin. Some research suggests that blue-green algae, like spirulina, may also have a mild blood-sugar-lowering effect of its own. So when you stack the two together, you could end up lowering your blood sugar more than you intended.

That means a slightly higher chance of hypoglycemia (low blood sugar), which can show up as shakiness, sweating, dizziness, hunger, confusion, or a racing heartbeat. The evidence here is fairly modest and partly theoretical, so this isn't a reason to panic. If you'd like to try blue-green algae, just check your blood sugars a bit more closely at first and let your pharmacist or doctor know before you start.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. 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
  2. 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
  3. 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

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Blue-green Algae Also Interacts With Other Medications

Blue-green Algae has 326 moderate known drug interactions in our database — the Glimepiride one above is one of them. If you take anything else, check it against the full list below.

Moderate 326 No known interaction 2,504 (incl. Glimepiride)
Taking anything else?

Check Another of Your Medications Against Blue-green Algae

Covers the 2,830 medications we’ve checked against Blue-green Algae. Pick one to open its full report.

From our Q&A

Questions About Blue-green Algae or Glimepiride

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Blue-green Algae or Glimepiride, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Glimepiride

This page covers Blue-green Algae only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Glimepiride page lists 306 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Siberian Cocklebur (major), Acai (moderate), Adrafinil (moderate) and African Wild Potato (moderate).

By severity: 2 major · 256 moderate · 48 minor.

From our pharmacist’s overview on the Glimepiride page

“Glimepiride (Amaryl) is a sulfonylurea, a diabetes pill that prompts the pancreas to release insulin, so anything that further lowers blood sugar can tip you into hypoglycemia, and that describes most of this list. Of the 306 supplement and herbal ingredients on file, 239 can move blood sugar on their own.”

Reviewed by 2 · Jul 18, 2026

Open the Glimepiride interaction page

One more smart check

Taking Blue-green Algae as Part of a Dietary Supplement Product? Check It for Interactions

We hold 3,180 real supplement products containing Blue-green Algae, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Blue-green Algae. Your product may carry other ingredients that interact with Glimepiride too, on top of Blue-green Algae — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Blue-green Algae and Glimepiride Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Blue-green Algae
Top 10%

#82 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Glimepiride
Top half

#916 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Blue-green Algae

What is Blue-green Algae?

Blue-green Algae
  • General nutrition and energy
  • Antioxidant support
  • Cholesterol and metabolic health
  • Immune support
  • Weight management

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 health claims is limited, and some products can be contaminated with toxins or heavy metals, so quality testing matters. Talk to your pharmacist or doctor before using, especially during pregnancy or breastfeeding.

Read the full Blue-green Algae monograph & all interactions
Medication

About Glimepiride

What Is Glimepiride Used For?

Brand name: Amaryl

Glimepiride tablets are used to improve blood sugar control in adults with type 2 diabetes. It is always used together with a healthy diet and regular exercise — not as a standalone treatment.

Glimepiride is not appropriate for type 1 diabetes or diabetic ketoacidosis (a serious complication where the body produces high levels of blood acids called ketones), as it would not work in those situations.

See full Glimepiride drug information
Keep checking

Other Drugs & Blue-green Algae

Browse every other medication we’ve checked against Blue-green Algae — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
326Moderate
0Minor
2,503No known interaction
326 Moderate 2,503 No interaction
Moderate

326 interactions

Showing 60 of 326 moderate interactions — see all 326 on the Blue-green Algae page.

No interaction 2,503 drugs checked — show the list

We also checked Blue-green Algae against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,503 medications checked with no known interaction — see the full Blue-green Algae list.

See the full Blue-green Algae interactions page
See every supplement checked against Glimepiride, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

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

Keep exploring
Blue-green Algae monograph › Uses, safety, and every drug interaction in one place Glimepiride supplement interactions › Every supplement checked against Glimepiride, ranked by severity Glimepiride drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Blue-green Algae and Glimepiride Together: Common Questions

Can you take Blue-green Algae with Glimepiride?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Blue-green Algae and Glimepiride interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Glimepiride and Blue-green Algae?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.