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Overactive bladder (OAB)
Overactive bladder is a syndrome of urgency, with or without urgency incontinence, usually with frequency and nocturia, in the absence of infection or other pathology; treatment is stepwise — behavioural, drugs (an antimuscarinic or a beta-3 agonist), then botulinum toxin, sacral neuromodulation or tibial nerve stimulation.
Why it matters in the exam
The diagnosis is clinical: history, examination, urinalysis to exclude infection and haematuria, and a 3-day bladder diary. Post-void residual is measured when poor emptying is suspected or before a treatment that may cause retention. Urodynamics is not needed before first treatment. Behavioural treatment includes bladder training (gradual lengthening of intervals), fluid management, cutting caffeine and alcohol, weight loss and pelvic floor training to suppress urgency.
The exam asks about drug choice and side effects. Antimuscarinics (oxybutynin, solifenacin, tolterodine, trospium) cause dry mouth, constipation and blurred vision; contraindications: untreated narrow-angle glaucoma, retention and gastric retention. The 2024 AUA guideline stresses the link between anticholinergic burden and cognitive decline and dementia, so in older patients a beta-3 agonist is preferred. Trospium hardly crosses the blood-brain barrier. Mirabegron (25 to 50 mg daily) may raise blood pressure and inhibits CYP2D6; vibegron (75 mg daily) is another beta-3 agonist.
When drug treatment fails or is not tolerated: injection of onabotulinumtoxinA at a dose of 100 units into the bladder wall (risk of retention and need for self-catheterisation, and urinary infections), sacral neuromodulation (SNS) — an implant that stimulates the S3 root after a test phase — or percutaneous tibial nerve stimulation (PTNS) once a week for 12 weeks. Bladder augmentation or urinary diversion is reserved for rare, severe cases. Before botulinum injection the patient must be able and willing to self-catheterise.
Key points
- OAB = urgency, with or without leakage, without infection.
- First line — behavioural treatment.
- Drugs: antimuscarinic or beta-3; in older patients beta-3.
- Refractory: botulinum toxin 100 units, SNS or PTNS.
- Antimuscarinics are linked to cognitive decline.
Summary table
| Step | Treatment | Note |
|---|---|---|
| First | Bladder training, fluid management, pelvic floor | Always |
| Drugs | Antimuscarinic or beta-3 agonist | In older patients beta-3 is preferred |
| Drug-refractory | Botulinum toxin 100 units | Risk of retention and self-catheterisation |
| Drug-refractory | Sacral neuromodulation | Test phase before a permanent implant |
| Drug-refractory | Weekly PTNS for 12 weeks | Needs maintenance sessions |
A free exam question
בן 8 ,שנים .בריא בד"כ, סובל מהרטבת לילה. במהלך היום דחיפות במתן שתן ולפעמים בריחה של שתן יציאות תקינות מעולם לא נגמל לחלוטין. האב מדווח שסבל גם הוא מהרטבת לילה בילדות עד גיל 9 . בדיקה. גופנית תקינה, שתן כללית ותרבית תקין . מה הטיפול המועדף במקרה זה? (the question as examined, in Hebrew)
- א. פעמונית
- ב. Minirin (Desmopressin)
- ג. Novitropan (Oxybutynin)
- ד. Tofranil (Imipramine)
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Sources
- AUA/SUFU Guideline: Diagnosis and Treatment of Idiopathic Overactive Bladder, 2024 — Evaluation, behavioural, pharmacological and minimally invasive therapies
- EAU Guidelines on Non-neurogenic Female LUTS, 2025 edition — Overactive bladder
- Campbell-Walsh-Wein Urology, 12th edition (2020) — Overactive Bladder
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.