Difficulty urinating can be a result of anatomical abnormalities within the genitourinary tract. In men, enlargement of the prostate gland, due most commonly to benign prostatic hyperplasia and less commonly to prostate cancer, can cause difficulty urinating. In both men and women, difficulty urinating can result from neurological or muscular conditions that affect function of the bladder. When it becomes difficult to urinate, other symptoms such as dribbling (leaking or mild incontinence) and a weak urine stream may also be present. Certain medications can also cause problems with urination. Scar tissue from surgery or trauma can also cause problems with the flow of urine. Infections of the urinary tract or of the nervous system can also cause retention of urine.
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