Drug & supplement interaction

European Barberry + Pilocarpine

Pilocarpine brand names: Salagen, Pilocar, Vuity, Qlosi.

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

European Barberry has a moderate interaction with Pilocarpine. Theoretically, taking European barberry with cholinergic drugs might decrease the effects of cholinergic drugs.

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

European Barberry and Pilocarpine

Here is the interaction we found between these two, with the evidence behind it.

Moderate

CHOLINERGIC DRUGS

Why this applies to Pilocarpine

Pilocarpine falls under CHOLINERGIC DRUGS — the group European Barberry interacts with.

Theoretically, taking European barberry with cholinergic drugs might decrease the effects of cholinergic drugs.
In vitro evidence suggests that European barberry might have anticholinergic properties.
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 gist for pilocarpine (Salagen, Vuity): it works by boosting your body's cholinergic signaling to get your salivary glands flowing, which is exactly why it helps with dry mouth. European barberry contains berberine and other alkaloids that, at least in lab dishes, may push in the opposite direction with mild anticholinergic activity. So the theory is that barberry could blunt how well pilocarpine works, meaning less relief from dry mouth rather than a buildup of side effects.

I want to be honest: this is theoretical and based on test-tube data, not real patients, so it's nothing to panic over. Pilocarpine is not a prodrug, so the direction holds (weaker effect). Still, if you're using barberry, it's worth a quick chat with your pharmacist or doctor before mixing the two.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Shamsa F, Ahmadiani A, Khosrokhavar R. Antihistaminic and anticholinergic activity of barberry fruit (Berberis vulgaris) in the guinea-pig ileum. J Ethnopharmacol 1999;64:161-6. PubMed

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

European Barberry Also Interacts With Other Medications

European Barberry has 1,211 moderate known drug interactions in our database — the Pilocarpine one above is one of them. If you take anything else, check it against the full list below.

Moderate 1,211 No known interaction 1,619 (incl. Pilocarpine)
Taking anything else?

Check Another of Your Medications Against European Barberry

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

Everything else you take

See Every Supplement That Interacts With Pilocarpine

This page covers European Barberry only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Pilocarpine page lists 40 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Bacopa (moderate), Bael (moderate), Betel Nut (moderate) and Boxwood (moderate).

By severity: 1 major · 28 moderate · 11 minor.

From our pharmacist’s overview on the Pilocarpine page

“Pilocarpine stimulates the body's cholinergic system, whether as Salagen tablets for the dry mouth of Sjogren's or radiation treatment or as eye drops like Vuity, and its supplement list calls for real care. The one major-rated interaction among the 40 on file is activated charcoal, which soaks up the drug in the gut and can cut how mu…”

Reviewed by 2 · Jul 18, 2026

Open the Pilocarpine interaction page

One more smart check

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

We hold 2 real supplement products containing European Barberry, each one broken down to its full ingredient list — and combination products often carry several ingredients besides European Barberry. Your product may carry other ingredients that interact with Pilocarpine too, on top of European Barberry — 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 European Barberry and Pilocarpine 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 European Barberry
Top 25%

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

29 days ago today
Medication Pilocarpine
Steady interest

#1,732 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 European Barberry

What is European Barberry?

European Barberry
  • Digestive upset
  • Antimicrobial support
  • Blood sugar support
  • Cholesterol and metabolic support
  • Skin conditions

European barberry is a shrub whose root, bark, and berries contain berberine, a bitter plant alkaloid that has been studied mostly in isolated form. Some early research on berberine is promising for blood sugar and cholesterol, but high-quality evidence for the whole barberry herb is limited. Talk with your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Read the full European Barberry monograph & all interactions
Medication

About Pilocarpine

What Is Pilocarpine Used For?

Brand names: Salagen, Pilocar, Vuity, Qlosi

Pilocarpine is used in two main ways, depending on the product. Eye drops treat certain eye conditions. Tablets treat dry mouth.

Pilocarpine hydrochloride ophthalmic solution (the glaucoma product) is used to lower raised eye pressure in open-angle glaucoma or ocular hypertension. It is also used for acute angle-closure glaucoma, to prevent raised eye pressure after laser surgery, and to constrict the pupil (miosis). Vuity, Qlosi and a separate pilocarpine hydrochloride ophthalmic solution are used for presbyopia in adults. Pilocarpine hydrochloride tablets and Salagen tablets treat dry mouth from radiation therapy for head and neck cancer and dry mouth in Sjogren's syndrome.

See full Pilocarpine drug information Pilocarpine Hydrochloride NDC codes and packages
Keep checking

Other Drugs & European Barberry

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

0Major
1,211Moderate
0Minor
1,618No known interaction
1,211 Moderate 1,618 No interaction
Moderate

1,211 interactions

Showing 60 of 1,211 moderate interactions — see all 1,211 on the European Barberry page.

No interaction 1,618 drugs checked — show the list

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

Showing the 60 most looked-up of 1,618 medications checked with no known interaction — see the full European Barberry list.

See the full European Barberry interactions page
See every supplement checked against Pilocarpine, 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
European Barberry monograph › Uses, safety, and every drug interaction in one place Pilocarpine supplement interactions › Every supplement checked against Pilocarpine, ranked by severity Pilocarpine drug information › The full plain-English guide to this medication Pilocarpine Hydrochloride NDC codes and packages › Every package, labeler and price in the FDA directory 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 European Barberry and Pilocarpine Together: Common Questions

Can you take European Barberry with Pilocarpine?
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.
How serious is the European Barberry and Pilocarpine 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

Still Have a Question About Pilocarpine and European Barberry?

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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.