FLOMAX. See More. What is tamsulosin?
* Tamsulosin is in a class of drugs calledalpha-adrenergic blockers. Tamsulosin causes the blood vessels (veinsand arteries) to relax and expand, so that blood passes through themmore easily. This effect relaxes the muscles in the prostate andbladder neck, making it easier to urinate.
* Tamsulosin is used to treat benign prostatichyperplasia (enlarged prostate).
* Tamsulosin may also be used for purposes otherthan those listed in this medication guide.