Benign prostatic hyperplasia with a weak stream, hesitancy, dribbling, or getting up at night to pass urine. It is also used to help small kidney stones pass, and before or after a urinary catheter is removed.

The prostate and bladder neck are wrapped in smooth muscle held under tension by alpha-1A receptors. Tamsulosin blocks those receptors selectively, so that muscle relaxes and the outlet widens. It does not shrink the prostate, which is why symptoms return if it is stopped.

Dizziness, especially on standing, a blocked or runny nose, headache, tiredness, and a change in ejaculation, which may become reduced or absent. That change is harmless and reverses on stopping.

Tell any eye surgeon you take or have taken tamsulosin before cataract surgery, because it can make the iris floppy during the operation and the team needs to plan for it. Stand up slowly, particularly for the first doses, and take it after the same meal each day. Tell your doctor about low blood pressure, fainting, or severe liver or kidney disease, and do not combine it with medicines for erectile dysfunction without advice. It is a prescription medicine in Pakistan.