Drug & supplement interaction

Calumba + Metformin, Sitagliptin

Metformin, Sitagliptin brand names: Janumet, Janumet XR.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Calumba and Metformin, Sitagliptin 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 label for Metformin, Sitagliptin states a food rule worth keeping to, and 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.

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Interaction report

Calumba and Metformin, Sitagliptin

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, Sitagliptin and Calumba 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.

Calumba safety at a glance

Calumba overall Use caution Little modern safety data exists, so use it cautiously and ideally under professional guidance.
Pregnancy Avoid Safety is unknown, so it is best avoided during pregnancy.
Breastfeeding Avoid There is not enough information to consider it safe while breastfeeding.

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

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

Why No Interaction Is Listed for Metformin, Sitagliptin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Metformin, Sitagliptin is filed under 5 classifications — including organic cation transporter 2 (oct2) substrates, antidiabetes drugs, oral drugs. Calumba has documented interactions with 3 drug classes — the most serious being antacids (minor), h2-blockers (minor) and proton pump inhibitors (ppis) (minor) — and none of Metformin, Sitagliptin’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

Calumba Does Interact With Other Medications

Calumba has 36 minor known drug interactions in our database — Metformin, Sitagliptin isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Calumba

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

What to actually watch for

No Interaction Found — But Data Suggests Calumba and Metformin, Sitagliptin 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.

  • Vomiting Additional detail

    Calumba

    “Orally, large doses of calumba may cause vomiting and epigastric pain (18).”

    Calumba · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    Metformin, Sitagliptin

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

Effects for Metformin, Sitagliptin come from the ADVERSE REACTIONS section of its FDA label; effects for Calumba 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.

How to take them

Some Metformin, Sitagliptin Products Have a Food Rule — Calumba Should Not Break It

At least one FDA label for a product containing Metformin, Sitagliptin says to take it with food. If you take Calumba on an empty stomach out of habit, keep them separate — and take Metformin, Sitagliptin with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Metformin, Sitagliptin products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

2 DOSAGE AND ADMINISTRATION Take sitagliptin and metformin hydrochloride extended-release tablets orally once daily with a meal.

From the Dosage and Administration section of the FDA label we read for Metformin, Sitagliptin — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

Everything else you take

See Every Supplement That Interacts With Metformin, Sitagliptin

This page covers Calumba only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Metformin, Sitagliptin page lists 257 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 · 38 minor.

From our pharmacist’s overview on the Metformin, Sitagliptin page

“Many people prescribed metformin with sitagliptin (Janumet, Janumet XR) for type 2 diabetes also try herbs sold as blood sugar support, fenugreek among the most popular, and that habit is exactly where the risk on this page concentrates. Of 257 documented supplement interactions, 239 can push glucose in the same direction the medicatio…”

Reviewed by 2 · Jul 18, 2026

Open the Metformin, Sitagliptin interaction page

How much people look this up

Where Calumba and Metformin, Sitagliptin 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 Calumba
Steady interest

#1,230 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Metformin, Sitagliptin
Steady interest

#1,459 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 Calumba reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Calumba and Metformin, Sitagliptin 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 Calumba

What is Calumba?

  • Poor appetite
  • Digestive upset and indigestion
  • Nausea
  • Diarrhea
  • As a bitter tonic

Calumba is the dried root of an African climbing plant that has long been used as a bitter tonic to stimulate appetite and ease digestive complaints. Modern scientific evidence for these uses is very limited, and its safety has not been well studied, so it should be used cautiously and avoided during pregnancy and breastfeeding.

Jateorhiza palmata · Menispermaceae · Dried root · Dried root, powder, tincture, liquid extract, capsules

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

Calumba: dosing

There is no well-established standardized dose for Calumba. Traditional sources used the dried root, powder, tinctures, or liquid extracts, but reliable modern dosing guidelines do not exist.If you choose to use a Calumba product, follow the directions on the label and do not exceed them.

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

Read the full Calumba monograph & all interactions
Keep checking

Other Drugs & Calumba

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

0Major
0Moderate
36Minor
2,793No known interaction
Minor

36 interactions

No interaction 2,793 drugs checked — show the list
Evidence & sources

Calumba References

The 2 references that drive our Calumba 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. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

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 Calumba and Metformin, Sitagliptin Together: Common Questions

Is it safe to take Calumba with Metformin, Sitagliptin?
We do not list a known interaction between Calumba and Metformin, Sitagliptin. 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 Calumba and Metformin, Sitagliptin 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.
Should I take Calumba and Metformin, Sitagliptin at the same time of day?
At least one FDA label for a product containing Metformin, Sitagliptin says to take it with food. If you take Calumba on an empty stomach out of habit, keep them separate and take Metformin, Sitagliptin with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Metformin, Sitagliptin products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Calumba and Metformin, Sitagliptin combination checked?
Interactions in our licensed database are recorded against drug classes. Metformin, Sitagliptin is filed under 5 classifications, and Calumba has documented interactions with 3 drug classes — none of Metformin, Sitagliptin'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 Calumba interact with any other medications?
Yes. Calumba has 36 documented drug interactions in our database — Metformin, Sitagliptin 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, Sitagliptin interact with any supplements?
Yes. Metformin, Sitagliptin has documented interactions with 257 supplements in our database — Calumba is not one of them. The Metformin, Sitagliptin interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Metformin, Sitagliptin and Calumba?

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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.