A selective, reversible alpha-1 blocker which may be used in the pre-operative preparation of patients with phaeochromocytoma
a) phenylephrine
b) prazosin
c) clonidine
d) yohimbine
e) idazoxan
Answer:
b) prazosin
Explanation
Prazosin is a selective, reversible alpha-1 blocker, and has been used to manage hypertension, and even in pre-operative preparation of patients with phaeochromocytoma. It should not be used in heart failure. Other similar agents include doxazosin, terazosin.
Agents such as yohimbine and idazoxan are Alpha-2 blockers and are mainly experimental curiosities used to analyse alpha receptor subtypes.