FlomaxListen to pronunciation(FLOH-max)A drug used to treat urinary problems caused by an enlarged prostate. Flomax relaxes the muscles of the prostate and bladder, which helps the flow of urine. It is a type of alpha blocker. Also called tamsulosin hydrochloride.Search NCI's Dictionary of Cancer TermsStarts withContainsBrowse:ABCDEFGHIJKLMNOPQRSTUVWXYZ#