Medication · antimuscarinic urinary

Supplements and Tolterodine.

Every documented pair, every citation. Below: 1 documented pair grouped by mechanism.

Tolterodine, sold under the brand name Detrusitol XL, is an antimuscarinic agent for urinary urgency or overactive bladder.

Tolterodine is an antimuscarinic agent for urinary urgency or overactive bladder. The class blocks muscarinic acetylcholine receptors in the detrusor muscle, reducing involuntary contraction. UK prescribing includes solifenacin, tolterodine, oxybutynin, and mirabegron (technically a beta-3 agonist but in the same prescribing space). The supplement surface includes additive anticholinergic burden, which matters most in older patients given the cognitive decline signal that has emerged in long anticholinergic exposure data. Supplements with anticholinergic potential at high doses (some choline pathway compounds in reverse, certain antiemetic herbals) warrant care. Dry mouth. Constipation. Urinary retention. All three scale with dose. The NICE NG123 guideline pushes for review of indication and dose every six to twelve months, given the cognitive burden picture.

Below are the 1 documented pair we have explicitly assessed against Tolterodine in the Distil database: 1 amber. The pairs cluster around 1 mechanism: Cholinergic vs anticholinergic (opposing). Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not on this list is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by supplement, and the missing-item form at the bottom of the page routes any uncatalogued supplement into our next curation pass.

Documented interactions

Cholinergic vs anticholinergic (opposing)

Amber Huperzine A

Huperzine A raises acetylcholine while tolterodine blocks it, so each can work against the other. Huperzine A may make tolterodine less effective for bladder symptoms, and tolterodine may blunt any benefit from huperzine A. It is not dangerous, but the two are pulling in opposite directions, so it is worth a word with your prescriber.

PMID 29350336 · PMID 18425924 · BNF: Tolterodine

Reviewer-flagged: awaiting clinical-reviewer sign-off.

What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope (food-supplement interactions only; for drug-drug interactions, the BNF is authoritative). Use the checker below to surface any supplement, and submit a missing item if you take something we have not catalogued.

Loading database stats…

For adults over 18. This tool gives evidence-graded information, not medical advice. Always discuss changes with your GP, especially if you take any medication, are pregnant, breastfeeding, or have a serious health condition.

Your supplements

Type the supplement name. Click each match to add it.

Your medications

Brand or generic name works. Click each match to add it.

Anything we should know? (optional)

Pick any that apply. We adjust the findings where context changes the answer.

I confirm I am 18 or over. This tool gives evidence-graded information, not medical advice; always discuss changes with your GP or pharmacist.

Add at least one supplement and one medication to check.

Not sure where to start? Try one:

How we decide

How we grade severity, choose what's in scope, and what we exclude.

Every call on this page is reasoned. We publish the full rubric for severity tiers, the medication inclusion logic, the evidence grades we accept, and what we deliberately leave out. About three thousand words. Worth reading once if you use this tool more than occasionally.

Read the full methodology

Your whole stack

Want this checked across everything you take?

This page checks the pairs you enter. The personalised Distil report goes further:

the same graded, cited interaction check across your whole stack, not just the pairs you thought to type in
where your current routine may be leaving you short of your goals
the evidence-backed compounds worth adding, and the ones worth dropping

It's a paid report: £79, or £49 for the first 25 customers. The interactions check is one section of it, and you can read a real one in full before you buy.

See a real sample report

Something missing?

If a supplement or medication you take isn't in our autocomplete, tell us. We go through what people flag every week and add what's missing.

Thanks, that's logged. We go through flagged items every week.

Distil's interactions database is reviewed and updated every quarter. We grade evidence transparently and publish our methodology, including every database change, at /about/methodology. This tool is information, not a substitute for clinical judgement. If you take medication and supplements together, your GP or pharmacist can review your full regimen against your medical history. If you want a full personalised stack reasoned against this same database, the Distil report is the next step up.