Drug & supplement interaction

Colocynth + Trospium

Trospium brand names: Sanctura, Trosec, Regurin.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Colocynth and Trospium 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 Trospium states a food rule worth keeping to.

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Interaction report

Colocynth and Trospium

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 Trospium and Colocynth 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.

Colocynth safety at a glance

Colocynth overall Avoid Colocynth is a strong irritant and poison that can cause severe gut damage and death.
Pregnancy Avoid It may stimulate the uterus and is considered unsafe in pregnancy.
Breastfeeding Unsafe When used orally due to severe gastrointestinal toxicity; avoid using. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Trospium and Colocynth? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Trospium

Interactions in our licensed database are recorded against drug classes, not just single drug names. Trospium is filed under 3 classifications — urinary acidifying agents, anticholinergic drugs, oral drugs. Colocynth has documented interactions with 5 drug classes — the most serious being antidiabetes drugs (moderate), digoxin (lanoxin) (moderate) and diuretic drugs (moderate) — and none of Trospium’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

Colocynth Does Interact With Other Medications

Colocynth has 185 moderate known drug interactions in our database — Trospium 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 Colocynth

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

What to actually watch for

What Colocynth Itself Has Been Linked To

This is not an interaction — nothing below involves Trospium. It is the side-effect record for Colocynth on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Colocynth, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • Seizures / Kidney problems Worth acting on Additional detail

    “Orally, colocynth is generally regarded as unsafe. Topically, colocynth seems to be well tolerated when used short-term.

    Most Common Adverse Effects:

    Orally: Diarrhea.

    Serious Adverse Effects (Rare):

    Orally: Bloody diarrhea, hemorrhagic cystitis, kidney damage, convulsions, paralysis, death.”

    Colocynth · Natural Medicines adverse-effect record, reported in diarrhea.

  • Itching Additional detail

    “Topically, mild pruritus has been reported in one patient that used a sesame oil-based colocynth fruit extract in a small clinical study.”

    Colocynth · Natural Medicines adverse-effect record, reported in pruritus.

    1 source cited
    1. 98602. Heydari M, Homayouni K, Hashempur MH, Shams M. Topical Citrullus colocynthis (bitter apple) extract oil in painful diabetic neuropathy: A double-blind randomized placebo-controlled clinical trial. J Diabetes. 2016;8(2):246-52. DOI
  • Diarrhea Additional detail

    “Orally, ingestion of colocynth 0.6-1 grams can cause severe irritation of the gastric mucosa and bloody diarrhea (2,18). Cases of bloody diarrhea and intestinal cramps have been reported in case reports of individuals consuming the fresh fruit, the 'size of an orange' or unknown amounts of the extract. Colocynth ingestion can also cause acute toxic colitis.”

    Colocynth · Natural Medicines adverse-effect record, reported in diarrhea.

    5 sources cited
    1. 2. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    3. 98601. Khan SA, Shelleh HH, Bhat AR, Bhat KS. Colocynth toxicity. A possible cause of bloody diarrhea. Saudi Med J. 2003;24(8):904-6. DOI
    4. 10653. Goldfain D, Lavergne A, Galian A, et al. Peculiar acute toxic colitis after ingestion of colocynth: a clinicopathological study of three cases. Gut 1989;30:1412-18.. PubMed
    5. 98604. Huseini HF, Darvishzadeh F, Heshmat R, Jafariazar Z, Raza M, Larijani B. The clinical investigation of Citrullus colocynthis (L.) schrad fruit in treatment of Type II diabetic patients: a randomized, double blind, placebo-controlled clinical trial. Phytot

Everything above comes from the Natural Medicines adverse-effect record for Colocynth — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Trospium’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Trospium column appears here.

Special populations

Colocynth in Pregnancy & Breastfeeding

Lactation Unsafe

When used orally due to severe gastrointestinal toxicity; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

How to take them

Some Trospium Products Have a Food Rule — Colocynth Should Not Break It

At least one FDA label for a product containing Trospium says to take it on an empty stomach. Most supplements — Colocynth included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Trospium on its own and move Colocynth to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Trospium 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.

Trospium Chloride Extended-Release Capsules should be dosed with water on an empty stomach, at least one hour before a meal.

From the Dosage and Administration section of the FDA label we read for Trospium — where that label names a specific product, the instruction is that product's. See the Trospium drug page ›

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 Trospium

This page covers Colocynth only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Trospium page lists 47 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Henbane (major), Scopolia (major), Angel's Trumpet (moderate) and Bacopa (moderate).

By severity: 3 major · 33 moderate · 11 minor.

From our pharmacist’s overview on the Trospium page

“Trospium (Sanctura, Regurin) calms an overactive bladder by blocking acetylcholine, and most of the 47 supplements flagged against it press on that same nerve signal. Thirty carry anticholinergic activity of their own, adding dry mouth, constipation, blurred vision, and confusion, and two of the three major ratings sit in that group: h…”

Reviewed by 2 · Jul 18, 2026

Open the Trospium interaction page

One more smart check

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

We hold 2 real supplement products containing Colocynth, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Colocynth. Even though Colocynth itself has no known interaction with Trospium, 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 Colocynth and Trospium 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 Colocynth
Steady interest

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

29 days ago today
Medication Trospium
Steady interest

#2,319 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 Colocynth reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Colocynth and Trospium records this page draws on were last updated July 11, 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 Colocynth

What is Colocynth?

  • Constipation
  • Digestive complaints
  • Diabetes (traditional use)
  • Joint and nerve pain
  • Skin conditions

Colocynth is a bitter desert gourd used in traditional medicine mainly as a powerful laxative, but it is highly toxic and can cause severe, sometimes deadly poisoning even at small doses. There is not enough good human evidence to support its use, and most pharmacists would advise against taking it. If you are curious about it, talk to a doctor or pharmacist before using any product that contains it.

Citrullus colocynthis · Cucurbitaceae · Fruit (pulp), seeds, and root · Dried fruit pulp, powder, capsules, traditional and homeopathic preparations

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

Colocynth: dosing

There is no established safe dose of colocynth for general use, and most health authorities and pharmacists do not recommend taking it at all because of its toxicity. Never take raw colocynth fruit, pulp, or seeds.

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

Read the full Colocynth monograph & all interactions
Medication

About Trospium

What Is Trospium Used For?

Brand names: Sanctura, Trosec, Regurin

Trospium — available as tablets and extended-release capsules — is used to treat overactive bladder (OAB). It targets three main symptoms: the sudden, hard-to-control urge to urinate (urgency), leaking urine when that urge hits (urge urinary incontinence), and needing to urinate much more often than usual (urinary frequency).

Both Trospium Chloride Tablets and Trospium Chloride Extended-Release Capsules carry this indication. Your prescriber will choose the formulation that fits your schedule and health history.

See full Trospium drug information
Keep checking

Other Drugs & Colocynth

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

0Major
185Moderate
0Minor
2,644No known interaction
Moderate

185 interactions

Showing 60 of 185 moderate interactions — see all 185 on the Colocynth page.

No interaction 2,644 drugs checked — show the list
Evidence & sources

Colocynth References

The 9 references that drive our Colocynth 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. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  4. Osol and Farar. The Dispensatory of the United States of America. 25th ed. JB Lippincott Co., 1955.
  5. Goldfain D, Lavergne A, Galian A, et al. Peculiar acute toxic colitis after ingestion of colocynth: a clinicopathological study of three cases. Gut 1989;30:1412-18.. PubMed
  6. Li Y, Zheng M, Zhai X, et al. Effect of Gymnema Sylvester, Citrullus colocynthis and Artemisa absinthum on blood glucose and lipid profile in diabetic human. Acta Pol Pharm. 2015;72(5):981-5.
  7. Khan SA, Shelleh HH, Bhat AR, Bhat KS. Colocynth toxicity. A possible cause of bloody diarrhea. Saudi Med J. 2003;24(8):904-6. DOI
  8. Heydari M, Homayouni K, Hashempur MH, Shams M. Topical Citrullus colocynthis (bitter apple) extract oil in painful diabetic neuropathy: A double-blind randomized placebo-controlled clinical trial. J Diabetes. 2016;8(2):246-52. DOI
  9. Huseini HF, Darvishzadeh F, Heshmat R, Jafariazar Z, Raza M, Larijani B. The clinical investigation of Citrullus colocynthis (L.) schrad fruit in treatment of Type II diabetic patients: a randomized, double blind, placebo-controlled clinical trial. Phytot

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 Colocynth and Trospium Together: Common Questions

Is it safe to take Colocynth with Trospium?
We do not list a known interaction between Colocynth and Trospium. 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.
Should I take Colocynth and Trospium at the same time of day?
At least one FDA label for a product containing Trospium says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Trospium on its own and move Colocynth to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.
How was the Colocynth and Trospium combination checked?
Interactions in our licensed database are recorded against drug classes. Trospium is filed under 3 classifications, and Colocynth has documented interactions with 5 drug classes — none of Trospium'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 Colocynth interact with any other medications?
Yes. Colocynth has 185 documented drug interactions in our database — Trospium 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 Trospium interact with any supplements?
Yes. Trospium has documented interactions with 47 supplements in our database — Colocynth is not one of them. The Trospium 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 Trospium and Colocynth?

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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.