Uses: This medication is used in men to treat the symptoms of an enlarged prostate (benign prostatic hyperplasia-BPH). Tamsulosin is known as an alpha-blocker and works by relaxing muscles in the bladder and prostate. Relaxing these muscles helps to relieve symptoms of BPH such as difficulty in beginning the flow of urine, weak stream, and the need to urinate frequently or urgently (including during the middle of the night). This medication should not be used to treat high blood pressure. It should not be used by women or children.