Drug & supplement interaction

Saigon Cinnamon + Metformin

Metformin brand names: Glucophage, Metformin.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Saigon Cinnamon and Metformin in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Saigon Cinnamon and Metformin

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Metformin and Saigon Cinnamon in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Saigon Cinnamon safety at a glance

Saigon Cinnamon overall Use caution Generally safe as a food spice, but large supplement doses raise concerns mainly due to its high coumarin content.
Pregnancy Use caution Food amounts are likely fine, but avoid medicinal or supplement doses during pregnancy due to limited safety data.
Breastfeeding Use caution Food amounts are likely fine, but avoid concentrated supplement doses because safety has not been studied.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Metformin and Saigon Cinnamon? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Metformin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Metformin is filed under 5 classifications — including organic cation transporter 2 (oct2) substrates, antidiabetes drugs, oral drugs. Saigon Cinnamon has documented interactions with 1 drug class — the most serious being hepatotoxic drugs (moderate) — and none of Metformin’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Saigon Cinnamon Does Interact With Other Medications

Saigon Cinnamon has 370 moderate known drug interactions in our database — Metformin isn’t one of them. If you take anything else, check it against the full list below.

Moderate 370 No known interaction 2,460 (incl. Metformin)
Taking anything else?

Check Another of Your Medications Against Saigon Cinnamon

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

What to actually watch for

No Interaction Found — But Data Suggests Saigon Cinnamon and Metformin May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • Liver problems Worth acting on Additional detail

    Saigon Cinnamon

    “There is some concern about the safety of ingesting large amounts of Saigon cinnamon for extended durations due to its coumarin content. Saigon cinnamon contains higher levels of coumarin than other cinnamon species. In humans, very high doses of coumarin from 50-7000 mg daily can result in hepatotoxicity that resolves when coumarin is discontinued.”

    Saigon Cinnamon · Natural Medicines adverse-effect record, reported in myasthenia gravis.

    2 sources cited
    1. 92558. Wang YH, Avula B, Nanayakkara NP, Zhao J, Khan IA. Cassia cinnamon as a source of coumarin in cinnamon-flavored food and food supplements in the United States. J Agric Food Chem. 2013;61(18):4470-6. PubMed
    2. 15302. 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

    Metformin

    Listed in the ADVERSE REACTIONS section of the FDA label for Metformin. Read the label on DailyMed ›

Effects for Metformin come from the ADVERSE REACTIONS section of its FDA label; effects for Saigon Cinnamon come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Overlapping uses

What Metformin Is Prescribed For, and What Saigon Cinnamon Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Metformin is a prescription medicine with approved uses on its FDA label. Saigon Cinnamon is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Metformin is prescribed for: Metformin is used to improve blood sugar (glucose) control in people with type 2 diabetes mellitus. It is always used together with diet and exercise, not instead of them. Metformin hydrochloride tablets and oral solution are approved for adults and children 10 years and older. Metformin hydrochloride extended-release tablets — including brands such as Fortamet, Glumetza, and Metformin Hydrochloride Extended Release — are approved for adults only.

Saigon Cinnamon has been studied for:

  • Diabetes studied, not established Saigon Cinnamon has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Saigon Cinnamon for diabetes

    Although there has been interest in using oral Saigon cinnamon for diabetes, there is insufficient reliable information about the clinical effects of Saigon cinnamon for this condition.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Metformin on your own; if you are taking Saigon Cinnamon for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Saigon Cinnamon or Metformin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Saigon Cinnamon or Metformin, 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 Metformin

This page covers Saigon Cinnamon only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Metformin page lists 258 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), African Wild Potato (moderate) and Agaricus Mushroom (moderate).

By severity: 2 major · 217 moderate · 39 minor.

From our pharmacist’s overview on the Metformin page

“Siberian cocklebur is the ingredient I most want anyone taking metformin (Glucophage) to know about. It has caused severe low blood sugar in people, documented in humans, and it should not be combined with any glucose-lowering medication.”

Reviewed by 2 · Jul 18, 2026

Open the Metformin interaction page

One more smart check

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

We hold 4 real supplement products containing Saigon Cinnamon, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Saigon Cinnamon. Even though Saigon Cinnamon itself has no known interaction with Metformin, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Saigon Cinnamon and Metformin 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 Saigon Cinnamon
Steady interest

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

29 days ago today
Medication Metformin
Top 1%

#29 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Saigon Cinnamon reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Saigon Cinnamon and Metformin records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Saigon Cinnamon

What is Saigon Cinnamon?

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

Saigon cinnamon is a flavorful spice from a Cinnamomum tree grown mainly in Vietnam, and it is a type of 'cassia' cinnamon. Some people use it for blood sugar and digestion, but the human evidence is limited. Because cassia cinnamons like this one are high in a compound called coumarin, regularly taking large supplement doses may be hard on the liver in sensitive people, so use food amounts and check with your pharmacist before taking concentrated products.

Cinnamomum loureiroi · Lauraceae · Inner bark (and bark essential oil) · Ground spice, sticks (quills), capsules, extracts, tea, essential oil

An interaction check asks whether these two react with each other — it does not ask whether Saigon Cinnamon is a good idea for someone in your situation. Here is what our Saigon Cinnamon record says about it on its own.

Saigon Cinnamon: dosing

There is no well-established standardized dose for Saigon cinnamon, and product strengths vary widely. Studies on cinnamon have used different amounts and forms, making it hard to recommend a single reliable dose.If you choose to use a supplement, the safest approach is to follow the directions on the product label and not exceed them.

From our Saigon Cinnamon monograph — the full record covers uses, side effects and every documented interaction.

Read the full Saigon Cinnamon monograph & all interactions
Medication

About Metformin

What Is Metformin Used For?

Brand names: Glucophage, Metformin

Metformin is used to improve blood sugar (glucose) control in people with type 2 diabetes mellitus. It is always used together with diet and exercise, not instead of them.

Metformin hydrochloride tablets and oral solution are approved for adults and children 10 years and older. Metformin hydrochloride extended-release tablets — including brands such as Fortamet, Glumetza, and Metformin Hydrochloride Extended Release — are approved for adults only.

See full Metformin drug information
Keep checking

Other Drugs & Saigon Cinnamon

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

0Major
370Moderate
0Minor
2,459No known interaction
370 Moderate 2,459 No interaction
Moderate

370 interactions

Showing 60 of 370 moderate interactions — see all 370 on the Saigon Cinnamon page.

No interaction 2,459 drugs checked — show the list

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

Showing the 60 most looked-up of 2,459 medications checked with no known interaction — see the full Saigon Cinnamon list.

See the full Saigon Cinnamon interactions page
See every supplement checked against Metformin, ranked by severity
Evidence & sources

Saigon Cinnamon References

The 4 references that drive our Saigon Cinnamon monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  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. Wang YH, Avula B, Nanayakkara NP, Zhao J, Khan IA. Cassia cinnamon as a source of coumarin in cinnamon-flavored food and food supplements in the United States. J Agric Food Chem. 2013;61(18):4470-6. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Saigon Cinnamon and Metformin Together: Common Questions

Is it safe to take Saigon Cinnamon with Metformin?
We do not list a known interaction between Saigon Cinnamon and Metformin. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Saigon Cinnamon and Metformin have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Are Saigon Cinnamon and Metformin used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Saigon Cinnamon in each. That is a conversation for your prescriber, especially if Metformin is being adjusted to a target.
How was the Saigon Cinnamon and Metformin combination checked?
Interactions in our licensed database are recorded against drug classes. Metformin is filed under 5 classifications, and Saigon Cinnamon has documented interactions with 1 drug class — none of Metformin's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Saigon Cinnamon interact with any other medications?
Yes. Saigon Cinnamon has 370 documented drug interactions in our database — Metformin is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Metformin interact with any supplements?
Yes. Metformin has documented interactions with 258 supplements in our database — Saigon Cinnamon is not one of them. The Metformin interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Saigon Cinnamon monograph Uses, safety profile, and every drug interaction in one place Metformin drug information The full plain-English guide to this medication Metformin supplement interactions Every supplement checked against Metformin, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 4 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Metformin and Saigon Cinnamon?

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.