Bladder spasms induced by involuntary bladder contractions are a distressing symptom affecting 7-27% of men and 9-43% of women. Very ill patients may develop bladder spasms as a complication from genitourinary malignancies, indwelling catheters, or other medical issues. For some patients, contractions can be incapacitating and associated with urinary incontinence.

Common etiologies of bladder spasms include: a urinary tract infection (UTI); ingestion of chemical irritants, like diet soda or caffeine; constipation; obstruction of the bladder outflow tract (e.g., non-emptying catheter from blood clots); disinhibition from interruption of upper motor neurons; or irritation of the detrusor muscle from a tumor, catheter, or intramural stone. Medications can also lead to spasms either by bladder irritation (e.g., diuretics) or disruption of the detrusor muscle or bladder outlet (e.g., opioids, anticholinergics, benzodiazepines, NSAIDs).

Clinical Evaluation
- Determine if the bladder is emptying properly. If not, consider urethral catheterization (see Clinical Management, below).
- A portable ultrasound can be used to check the post-void residual (PVR) urine in the bladder. In the situation of acute bladder spasm it is important to look for an acute increase in PVR values (e.g., from 200 mL to 450 mL).
- Physical examination of the suprapubic area for bladder fullness as well as patient report can help evaluate bladder emptying.
- Evaluate for easily reversible causes (e.g., stop offending agents, treat constipation).
- Exclude UTI with a urinalysis (UA). If an indwelling catheter is in place, it should be changed, and the culture sent from the new catheter as soon as it is placed.

Clinical Management
Multiple non-pharmacologic and pharmacologic therapies exist and may be used in combination. In general, start with the least invasive approach. Diagnostic imaging and/or a urology referral is necessary in refractory cases.

Most experts prefer intermittent urethral catheterization for ambulatory patients with longer prognoses to minimize infection risk. In dying patients, indwelling catheterization is often preferred by patients, clinicians, and caregivers.

Interventional procedures include:
- Onabotulinum toxin injection to the detrusor muscle
- surgical resection of bladder tumors or lithotripsy of stones
- pelvic physical therapy
- use of intravesical baclofen or bupivacaine infused via an indwelling catheter

See reference for more information.

Adapted from De E, Gomery P, Rosenberg LB. Bladder spasms. Palliative Care Network of Wisconsin. Fast facts and concepts #337. Internet. Accessed on May 22, 2018.