[Preoperative management of pheochromocytoma with prazosin: report of three cases].

We used prazosin (alpha-blocker) for preoperative management of three patients with pheochromocytoma. All patients had episodic hypertension with headache and palpitation. The first dose of prazosin caused blood pressure to drop in one of three patients, but no significant hypotension was observed. By the daily dose of 6-8 mg prazosin with or without propranolol, subjective symptoms of the patients were improved and the frequency of the hypertensive attack was decreased Operations were carried out without significant complications, but phentramine and nitroprusside were required because of rapid rise of blood pressure during induction of anesthesia and surgical manipulation.