Drug & supplement interaction

Black Currant + Trospium

Trospium brand names: Sanctura, Trosec, Regurin.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Black Currant 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

Black Currant 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 Black Currant 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.

Black Currant safety at a glance

Black Currant overall Use caution The berry is safe as a food, but concentrated supplements are less studied and should be used carefully.
Pregnancy Use caution Eating the berry in food amounts is likely fine, but supplements lack safety data, so check with your doctor first.
Breastfeeding Use caution Food amounts are probably okay, but there is not enough information on concentrated supplements, so use caution.

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

Still wondering about combining Trospium and Black Currant? 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. Black Currant has documented interactions with 2 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate) and phenothiazines (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

Black Currant Does Interact With Other Medications

Black Currant has 140 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 Black Currant

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

What to actually watch for

What Black Currant Itself Has Been Linked To

This is not an interaction — nothing below involves Trospium. It is the side-effect record for Black Currant on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Black Currant, this list is the first place to look.

  • Diarrhea Additional detail

    “Of 2154 patients with hyperlipidemia taking black currant seed oil 1.8 grams twice daily for 6 weeks, 8 reports of mild diarrhea were considered related to the supplement. These adverse reactions were reported 2-10 days after beginning treatment with black currant seed oil.”

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

    1 source cited
    1. 17638. Fa-lin Z, Zhen-yu W, Yan H, et al. Efficacy of blackcurrant oil soft capsule, a Chinese herbal drug, in hyperlipidemia treatment. Phytother Res 2010;24 Suppl 2:S209-13. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Black Currant — 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.

How to take them

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

At least one FDA label for a product containing Trospium says to take it on an empty stomach. Most supplements — Black Currant 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 Black Currant 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.

From our Q&A

Questions About Black Currant or Trospium

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

This page covers Black Currant 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 Black Currant as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,265 real supplement products containing Black Currant, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Black Currant. Even though Black Currant 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 Black Currant 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 Black Currant
Top 25%

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

29 days ago today
Medication Trospium
Steady interest

#2,205 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 Black Currant reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Black Currant and Trospium 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 Black Currant

What is Black Currant?

Black Currant
  • Dry eyes and eye strain
  • Joint pain and inflammation
  • Immune and general wellness support
  • Cardiovascular health
  • Skin conditions (such as dry skin or eczema)

Black currant is a nutritious berry that is rich in vitamin C and antioxidants, and its seed oil contains the omega-6 fatty acid GLA. While it is enjoyed safely as a food and is popular as a supplement, solid human evidence for most health claims is still limited. Talk with your pharmacist or doctor before using concentrated supplements, especially if you are pregnant, nursing, or have a medical condition.

Ribes nigrum · Grossulariaceae · Berries (fruit), seeds (seed oil), and leaves · Whole berries, juice, capsules, seed oil softgels, dried leaf for tea, extracts

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

Black Currant: dosing

There is no official standardized dose for black currant supplements. The right amount can vary depending on the form (berry, juice, seed oil, or leaf) and the product's strength.Because doses are not well established, the safest approach is to follow the directions on the product label and not exceed them.

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

Read the full Black Currant 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 & Black Currant

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

0Major
140Moderate
0Minor
2,689No known interaction
Moderate

140 interactions

Showing 60 of 140 moderate interactions — see all 140 on the Black Currant page.

No interaction 2,689 drugs checked — show the list
Evidence & sources

Black Currant References

The 6 references that drive our Black Currant 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. Guivernau M, Meza N, Barja P, Roman O. Clinical and experimental study on the long-term effect of dietary gamma-linolenic acid on plasma lipids, platelet aggregation, thromboxane formation, and prostacyclin production. Prostaglandins Leukot Essent Fatty A PubMed
  2. Fa-lin Z, Zhen-yu W, Yan H, et al. Efficacy of blackcurrant oil soft capsule, a Chinese herbal drug, in hyperlipidemia treatment. Phytother Res 2010;24 Suppl 2:S209-13. PubMed
  3. Holman CP and Bell AF. A trial of evening primrose oil in the treatment of chronic schizophrenia. J Orhtomolecular Psych 1983;12:302-304.
  4. Vaddadi KS. The use of gamma-linolenic acid and linoleic acid to differentiate between temporal lobe epilepsy and schizophrenia. Prostaglandins Med 1981;6(4):375-379. PubMed
  5. Norred, C. L. and Brinker, F. Potential coagulation effects of preoperative complementary and alternative medicines. Alt Ther 2001;7(6):58-67.
  6. Puri BK. The safety of evening primrose oil in epilepsy. Prostaglandins Leukotrienes Essential Fatty Acids 2007;77:101-3. 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 Black Currant and Trospium Together: Common Questions

Is it safe to take Black Currant with Trospium?
We do not list a known interaction between Black Currant 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 Black Currant 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 Black Currant 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 Black Currant and Trospium combination checked?
Interactions in our licensed database are recorded against drug classes. Trospium is filed under 3 classifications, and Black Currant has documented interactions with 2 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 Black Currant interact with any other medications?
Yes. Black Currant has 140 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 — Black Currant 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 Black Currant?

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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.