Drug & supplement interaction

Cassia Cinnamon + Rosiglitazone Maleate

Rosiglitazone Maleate brand name: Avandia.

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

Rosiglitazone Maleate falls into 2 drug categories that Cassia Cinnamon can interact with; the most serious is rated moderate. Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cassia Cinnamon and Rosiglitazone Maleate

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Cassia Cinnamon interacts with whole categories of medication. Rosiglitazone Maleate falls into 2 of those categories, so it can interact with Cassia Cinnamon in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

HEPATOTOXIC DRUGS

1 of 2

Why this applies to Rosiglitazone Maleate

Rosiglitazone Maleate falls under HEPATOTOXIC DRUGS — the group Cassia Cinnamon interacts with.

Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.
There is some concern that ingesting large amounts of cassia cinnamon for an extended duration might cause hepatotoxicity in some people. Cassia cinnamon contains coumarin, which can cause hepatotoxicity in animal models. In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin use is discontinued. Lower amounts might also cause liver problems in sensitive people, such as those with liver disease or those taking potentially hepatotoxic agents.
Severity Moderate Likelihood Possible Evidence D

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 situation with cassia cinnamon and your Avandia (rosiglitazone). This isn't about cinnamon changing how the drug works in your blood sugar. Instead, both can put a little stress on your liver. Cassia cinnamon naturally contains coumarin, and in large, regular supplement doses over time, that coumarin may strain the liver in sensitive people. Rosiglitazone, on its own, can occasionally affect liver enzymes too, so the worry is an additive burden.

To be clear, this is a theoretical concern based on how these things behave, not a proven problem. Sprinkling cinnamon on your oatmeal is not the issue here, high-dose supplements taken daily for months are. Watch for things like unusual tiredness, yellowing skin or eyes, dark urine, or belly pain, and check with your pharmacist or doctor before starting a cinnamon supplement.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Press release. Cinnamon capsules to reduce blood sugar are medicinal products! Efficacy has not been scientifically proven - some products contain high levels of coumarin. Federal Institute of Risk Assessment (BfM), Germany, November 11, 2006. Available a
  2. Felter SP, Vassallo JD, Carlton BD, Daston GP. A safety assessment of coumarin taking into account species-specificity of toxicokinetics. Food Chem Toxicol 2006;44:462-75. PubMed
  3. Choi, J., Lee, K. T., Ka, H., Jung, W. T., Jung, H. J., and Park, H. J. Constituents of the essential oil of the Cinnamomum cassia stem bark and the biological properties. Arch Pharm Res 2001;24(5):418-423.
  4. Brancheau D, Patel B, Zughaib M. Do cinnamon supplements cause acute hepatitis? Am J Case Rep 2015;16:250-4. PubMed
Moderate

ANTIDIABETES DRUGS

2 of 2

Rosiglitazone Maleate also falls under ANTIDIABETES DRUGS.

Theoretically, cassia cinnamon may have additive effects with antidiabetes drugs.
Cassia cinnamon may lower blood glucose levels, and have additive effects in patients treated with antidiabetic agents. Dose adjustments to diabetes medications might be necessary.
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: both cassia cinnamon and rosiglitazone (Avandia) can nudge your blood sugar in the same direction, which is downward. When you stack two blood-sugar-lowering helpers together, their effects can add up. The concern isn't that cinnamon harms the drug, it's that the combined push could drop your sugar a little lower than expected.

Honestly, the evidence that cinnamon meaningfully lowers blood sugar is weak and mixed, so for most people this is a small, theoretical worry. The amount you sprinkle on toast or oatmeal almost certainly won't matter. Concentrated daily supplement doses are where I'd pay attention. Watch for shakiness, sweating, or feeling lightheaded, check your readings, and chat with your pharmacist or doctor before adding a high-dose cinnamon supplement.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Khan A, Safdar M, Ali Khan M, et al. Cinnamon improves glucose and lipids of people with type 2 diabetes. Diabetes Care 2003;26:3215-8. PubMed
  2. Crawford P. Effectiveness of cinnamon for lowering hemoglobin A1C in patients with type 2 diabetes: a randomized, controlled trial. J Am Board Fam Med 2009;22:507-12. PubMed
  3. Akilen, R., Tsiami, A., Devendra, D., and Robinson, N. Glycated haemoglobin and blood pressure-lowering effect of cinnamon in multi-ethnic Type 2 diabetic patients in the UK: a randomized, placebo-controlled, double-blind clinical trial. Diabet.Med. 2010; PubMed
  4. Lu T, Sheng H Wu J Cheng Y Zhu J Chen Y. Cinnamon extract improves fasting blood glucose and glycosylated hemoglobin level in Chinese patients with type 2 diabetes. Nutr Res. 2012;32(6):408-412. PubMed
  5. Stoecker BR, Zhan Z, Luo R, et al. Cinnamon extract lowers blood glucose in hyperglycemic subjects. FASEB J. 2010;22:722.1 (Abstract only). DOI

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

Cassia Cinnamon Also Interacts With Other Medications

Cassia Cinnamon has 443 moderate known drug interactions in our database — the Rosiglitazone Maleate one above is among them. If you take anything else, check it against the full list below.

Moderate 443 No known interaction 2,387 (incl. Rosiglitazone Maleate)
Taking anything else?

Check Another of Your Medications Against Cassia Cinnamon

Covers the 2,830 medications we’ve checked against Cassia Cinnamon. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Rosiglitazone Maleate

This page covers Cassia Cinnamon only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Rosiglitazone Maleate page lists 314 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Siberian Cocklebur (major), Wine (major) and Acai (moderate).

By severity: 4 major · 266 moderate · 44 minor.

From our pharmacist’s overview on the Rosiglitazone Maleate page

“Rosiglitazone (Avandia) lowers blood sugar in type 2 diabetes, and most of the 314 supplements and herbs on this page pull on that same lever. Some 239 can move blood glucose on their own, so adding one risks hypoglycemia, the shakiness, sweating, and confusion of sugar falling too low.”

Reviewed by 2 · Jul 18, 2026

Open the Rosiglitazone Maleate interaction page

One more smart check

Taking Cassia Cinnamon as Part of a Dietary Supplement Product? Check It for Interactions

We hold 3,249 real supplement products containing Cassia Cinnamon, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cassia Cinnamon. Your product may carry other ingredients that interact with Rosiglitazone Maleate too, on top of Cassia Cinnamon — 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 Cassia Cinnamon and Rosiglitazone Maleate 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 Cassia Cinnamon
Top 5%

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

29 days ago today
Medication Rosiglitazone Maleate
Top 5%

#60 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 Cassia Cinnamon

What is Cassia Cinnamon?

Cassia Cinnamon
  • Blood sugar support
  • Digestive upset
  • Antioxidant support
  • Flavoring and culinary use
  • Antimicrobial

Cassia cinnamon is the common, inexpensive cinnamon used in cooking, and it is also taken as a supplement, most often for blood sugar support. The evidence for its health benefits is mixed and far from proven, and because cassia is naturally high in coumarin, taking large amounts regularly may stress the liver. Use food amounts freely, but talk with a pharmacist or doctor before using high-dose supplements.

Read the full Cassia Cinnamon monograph & all interactions
Medication

About Rosiglitazone

What Is Rosiglitazone Used For?

Brand name: Avandia

  • Rosiglitazone is used along with a diet and exercise program and sometimes with one or more other medications to treat type 2 diabetes (condition in which the body does not use insulin normally and therefore cannot control the amount of sugar in the blood). Rosiglitazone is in a class of medications called thiazolidinediones. It works by increasing the body's sensitivity to insulin, a natural substance that helps control blood sugar levels. Rosiglitazone is not used to treat type 1 diabetes (condition in which the body does not produce insulin and therefore cannot control the amount of sugar in the blood) or diabetic ketoacidosis (a serious condition that may occur if high blood sugar is not treated).

  • Over time, people who have diabetes and high blood sugar can develop serious or life-threatening complications, including heart disease, stroke, kidney problems, nerve damage, and eye problems. Taking medication(s), making lifestyle changes (e.g., diet, exercise, quitting smoking), and regularly checking your blood sugar may help to manage your diabetes and improve your health. This therapy may also decrease your chances of having a heart attack, stroke, or other diabetes-related complications such as kidney failure, nerve damage (numb, cold legs or feet; decreased sexual ability in men and women), eye problems, including changes or loss of vision, or gum disease. Your doctor and other healthcare providers will talk to you about the best way to manage your diabetes.

See full Rosiglitazone drug information
Keep checking

Other Drugs & Cassia Cinnamon

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

0Major
443Moderate
0Minor
2,386No known interaction
443 Moderate 2,386 No interaction
Moderate

443 interactions

Showing 60 of 443 moderate interactions — see all 443 on the Cassia Cinnamon page.

No interaction 2,386 drugs checked — show the list

We also checked Cassia Cinnamon against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,386 medications checked with no known interaction — see the full Cassia Cinnamon list.

See the full Cassia Cinnamon interactions page
See every supplement checked against Rosiglitazone Maleate, 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
Cassia Cinnamon monograph › Uses, safety, and every drug interaction in one place Rosiglitazone Maleate supplement interactions › Every supplement checked against Rosiglitazone Maleate, ranked by severity Rosiglitazone 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 Cassia Cinnamon and Rosiglitazone Maleate Together: Common Questions

Can you take Cassia Cinnamon with Rosiglitazone Maleate?
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.
Why are there 2 interactions listed for Cassia Cinnamon and Rosiglitazone Maleate?
Rosiglitazone Maleate belongs to more than one drug category, and Cassia Cinnamon interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Cassia Cinnamon and Rosiglitazone Maleate 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

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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.