Antimuscarinic Pregnancy: Not recommended during pregnancy — no adequate data in pregnant women and animal studies have shown reproductive toxicity; the potential risk for humans is unknown. Tolterodine should be avoided during lactation.

Tolterodine

Brand names: Detrusitol

Tolterodine is an antimuscarinic used for the symptoms of overactive bladder.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 2 mg twice daily

Route: Oral (film-coated tablet)

Frequency: Twice daily

§4.2: adults including the elderly — 2 mg twice daily, except in patients with impaired liver function or severely impaired renal function (GFR ≤ 30 ml/min), for whom the recommended dose is 1 mg twice daily. In case of troublesome side effects the dose may be reduced from 2 mg to 1 mg twice daily. The effect of treatment should be re-evaluated after 2–3 months. Paediatric: efficacy has not been demonstrated in children, so this product is not recommended for children (no per-kg regimen — paedDose null). §4.4: concomitant treatment with potent CYP3A4 inhibitors should be avoided. IMPORTANT: the fetched UK SPC is the IMMEDIATE-RELEASE tablet (twice daily). The US label in the bundle is a different formulation — 4 mg extended-release capsules once daily (2 mg once daily with mild/moderate hepatic impairment, severe renal impairment or potent CYP3A4 inhibitors) — so do not merge the two; a UK prolonged-release 4 mg once-daily product would need its own SPC.

Dose adjustments

Renal

Severely impaired renal function (GFR ≤ 30 ml/min): 1 mg twice daily (the same reduced dose applies to impaired liver function).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

• 4 mg capsules taken orally once daily with water and swallowed whole. ( 2.1 ) • 2 mg capsules taken orally once daily with water and swallowed whole in the presence of: o mild to moderate hepatic impairment (Child-Pugh class A or B) ( 2.2 ) o severe renal impairment [Creatinine Clearance (CCr) 10-30 mL/min] ( 2.2 ) o drugs that are potent CYP3A4 inhibitors. ( 2.2 ) • Tolterodine tartrate extended-release capsules are not recommended for use in patients with CCr <10 mL/min. ( 2.2 ) • Tolterodine tartrate extended-release capsules are not recommended for use in patients with severe hepatic impairment (Child-Pugh Class C). ( 2.2 ) 2.1 Dosing Information The recommended dose of tolterodine …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2024-12-14. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Contraindications

Urinary retention
Uncontrolled narrow angle glaucoma
Myasthenia gravis
Known hypersensitivity to tolterodine or excipients
Severe ulcerative colitis
Toxic megacolon

Side effects

Dry mouth (very common — 35% of treated patients)
Headache (very common — 10.1%)
Dyspepsia, constipation, abdominal pain, flatulence, vomiting, diarrhoea
Dry eyes and abnormal vision including abnormal accommodation
Dizziness, somnolence and paraesthesia
Fatigue, chest pain and peripheral oedema

Interactions

Potent CYP3A4 inhibitors — concomitant systemic macrolides (erythromycin, clarithromycin), antifungals (ketoconazole, itraconazole) and antiproteases are not recommended, due to increased serum tolterodine concentrations in poor CYP2D6 metabolisers and risk of overdosage
Other medicines with antimuscarinic properties — more pronounced therapeutic effect and side effects
Muscarinic cholinergic receptor agonists — may reduce the therapeutic effect of tolterodine
Prokinetics such as metoclopramide and cisapride — their effect may be decreased by tolterodine
Medicines known to prolong the QT interval, including class IA (quinidine, procainamide) and class III (amiodarone, sotalol) antiarrhythmics — use tolterodine with caution (§4.4)
Fluoxetine (potent CYP2D6 inhibitor) — no clinically significant interaction; no interaction shown with warfarin or combined oral contraceptives

Clinical monograph

How it works

It blocks muscarinic receptors in the bladder, reducing detrusor overactivity.

Prescribing in practice

Antimuscarinic effects (dry mouth, constipation, blurred vision, and — in older people — confusion and falls) limit it; weigh the overall anticholinergic burden.
Avoid in narrow-angle glaucoma, significant urinary retention and gastrointestinal obstruction.
It can prolong the QT interval; reduce the dose in hepatic/renal impairment and with strong CYP inhibitors.

Monitoring

Review symptom benefit and anticholinergic effects, particularly cognition in older patients.

Counselling the patient

Dry mouth and constipation are common.
Report difficulty passing urine or new confusion.

Evidence & guidelines

An antimuscarinic option for overactive bladder (NICE NG123), mindful of anticholinergic burden in older people.

Reference: NICE NG123; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Drugs

Pathways