Flomax, Generic Flomax, Tamsulosin Hydrochloride is in a class of drugs called alpha-adrenergic blockers.

Tamsulosin Hydrochloride causes the blood vessels (veins and arteries) to relax and expand, so that blood passes through them more easily.

This effect relaxes the muscles in the prostate and bladder neck, making it easier to urinate.

Tamsulosin Hydrochloride is used to treat benign prostatic hyperplasia (enlarged prostate).