Urinary retention

Urinary retention
Other names	Ischuria, bladder failure, bladder obstruction
Urinary retention with greatly enlarged bladder as seen by CT scan.
Specialty	Emergency medicine, urology
Symptoms	Sudden onset: Inability to urinate, low abdominal pain[1] Long term: Frequent urination, loss of bladder control, urinary tract infection[1]
Types	Acute, chronic[1]
Causes	Blockage of the urethra, nerve problems, certain medications, weak bladder muscles[1]
Diagnostic method	Amount of urine in the bladder post urination[1]
Treatment	Catheter, urethral dilation, urethral stents, surgery[1]
Medication	Alpha blockers such as terazosin, 5α-reductase inhibitors such as finasteride[1]
Frequency	6 per 1,000 per year (males > 40 years old)[1]

Urinary retention is an inability to completely empty the bladder.^[1] Onset can be sudden or gradual.^[1] When of sudden onset, symptoms include an inability to urinate and lower abdominal pain.^[1] When of gradual onset, symptoms may include loss of bladder control, mild lower abdominal pain, and a weak urine stream.^[1] Those with long-term problems are at risk of urinary tract infections.^[1]

Causes include blockage of the urethra, nerve problems, certain medications, and weak bladder muscles.^[1] Blockage can be caused by benign prostatic hyperplasia (BPH), urethral strictures, bladder stones, a cystocele, constipation, or tumors.^[1] Nerve problems can occur from diabetes, trauma, spinal cord problems, stroke, or heavy metal poisoning.^[1] Medications that can cause problems include anticholinergics, antihistamines, tricyclic antidepressants, cyclobenzaprine, diazepam, nonsteroidal anti-inflammatory drugs (NSAID), amphetamines, and opioids.^[1][2] Diagnosis is typically based on measuring the amount of urine in the bladder after urinating.^[1]

Treatment is typically with a catheter either through the urethra or lower abdomen.^[1][3] Other treatments may include medication to decrease the size of the prostate, urethral dilation, a urethral stent, or surgery.^[1] Males are more often affected than females.^[1] In males over the age of 40 about 6 per 1,000 are affected a year.^[1] Among males over 80 this increases 30%.^[1]