DRUG CLASS AND MECHANISM: Terazosin belongs to a class of medications called alpha 1 blockers which relaxes the smooth muscles of the arteries, the prostate, and the bladder neck. Other alpha blockers in the same class of drugs include doxazosin (Cardura), alfuzosin (Uroxatral), tamsulosin (Flomax), and prazosin (Minipress). Relaxing the smooth muscles of the arteries lowers blood pressure. Relaxing the smooth muscles around the bladder neck relieves urinary obstruction caused by an enlarged prostate (prostate hypertrophy)

this is what i know of hytrin's use ... for prostate enlargement. i never hear of it used for RSD! that is something i will have to google!!!
Joan