<prompt> Alfa blocker useful in BPH is?PhentolaminePrazosinTolazolinePhenoxybenzamine  <response>: ANSWER: B PrazosinREF: Goodman and Gillman s 11TH edition page 172, 173, 183a BLOCKERSClassDrugsPharmacologicalActionsApplicationsUntoward EffectsNon selective classical a blockersPhenoxvbenzaminePhentolamineTolazolineDecrease in PVR and blood pressure VenodilationTreatment of catecholamine excess PheochromocytomaPostural hypotension Failure of ejaculationSelective cq blockersPrazosinTerazosinDoxazosinTrimazosinAlfuzosinTamsulosinDecrease in PVR and blood pressure Relax smooth muscles in neck of urinary bladder and in prostatePrimary hypertension. Increase urine flow in BPHPostural hypotensionPrazosin, the prototypic quinazoline a blocker, is a potent and selective a receptor antagonist. In treating benign prostatic hyperplasia BPH, doses from 1 to 5 mg twice daily typically are used. The twice-daily dosing requirement for prazosin is a disadvantage compared with newer a receptor antagonists. 