Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss of bladder control. Complications can include urinary tract infections, bladder stones, and chronic kidney problems.

The cause is unclear. Risk factors include a family history, obesity, type 2 diabetes, not enough exercise, and erectile dysfunction. Medications like pseudoephedrine, anticholinergics, and calcium channel blockers may worsen symptoms. The underlying mechanism involves the prostate pressing on the urethra and thereby making it difficult to pass urine out of the bladder. Diagnosis is typically based on symptoms and examination after ruling out other possible causes.

Treatment options include lifestyle changes, medications, a number of procedures, and surgery. In those with mild symptoms, weight loss, exercise, and decreasing caffeine intake are recommended, although the quality of the evidence for exercise is low. In those with more significant symptoms, medications may include alpha blockers such as terazosin or 5α-reductase inhibitors such as finasteride. Surgical removal of part of the prostate may be carried out in those who do not improve with other measures. Some herbal medicines that have been studied, such as saw palmetto, have not been shown to help. Other herbal medicines somewhat effective at improving urine flow include beta-sitosterol from Hypoxis rooperi (African star grass), pygeum (extracted from the bark of Prunus africana), pumpkin seeds (Cucurbita pepo), and stinging nettle (Urtica dioica) root.

About 105 million men are affected globally. BPH typically begins after the age of 40. Half of males age 50 and over are affected. After the age of 80, that figure climbs to as high as about 90% of males affected. Although prostate specific antigen levels may be elevated in males with BPH, the condition does not increase the risk of prostate cancer.