Overactive bladder
Overactive bladder is a clinical diagnosis of urinary urgency, usually with frequency and nocturia, with or without urge incontinence, in the absence of urinary tract infection or another identifiable cause, reflecting involuntary detrusor contraction during bladder filling. First-line treatment is behavioral therapy (bladder training with timed voiding, fluid and bladder-irritant modification), second-line is an antimuscarinic or a beta-3 agonist, and refractory cases proceed to intradetrusor onabotulinumtoxinA or sacral neuromodulation after confirming a normal postvoid residual.
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What this article covers
- Overview
Overactive bladder (OAB) is a symptom complex, not a structural diagnosis: urinary urgency, usually accompanied by frequency and nocturia, with or without urge incontinence, in the absence of urinary…
- Epidemiology
OAB is common and increases with age, though it can present in younger adults, as in a 32-year-old woman voiding 10-12 times daily with nocturia three to four times nightly and no dysuria.
- Risk factors
High caffeine or fluid intake, especially before bedtime: a common, modifiable contributor identified on a voiding diary.
- Pathophysiology
Involuntary detrusor contractions occur during bladder filling, generating urgency before the bladder is functionally full, unlike the normal suppression of detrusor activity until voluntary voiding.
- Clinical features
Urinary urgency is the defining, hallmark symptom: a sudden, compelling desire to void that is difficult to defer, typically accompanied by increased daytime frequency and nocturia.
- Differential diagnosis
Urinary tract infection: urgency and frequency plus dysuria and often pyuria/bacteriuria on urinalysis, unlike the absence of dysuria in OAB; see urinary-tract-infections-utis-including-pyelonephritis.
- Diagnosis
OAB is a clinical diagnosis established by the symptom complex of urgency, usually with frequency and nocturia, with or without urge incontinence, after urinary tract infection and other identifiable…
- Management
First, start behavioral therapy, the universal first-line treatment: reduce caffeine, spicy food, and other bladder irritants (especially before bedtime), and begin bladder training with timed…
- Complications
Complete urinary retention if antimuscarinic or beta-3 agonist therapy is started without first excluding an elevated postvoid residual.
- Prognosis
Most patients improve substantially with behavioral therapy alone or behavioral therapy plus a single second-line agent, without needing invasive treatment.
- Prevention
Limit caffeinated beverages, alcohol, and other bladder irritants, particularly in the hours before bedtime, to reduce urgency and nocturia.
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