Phentolamine (Regitine) Test in Cerebrovascular Accidents

A "POSITIVE" phentolamine (Regitine) test has been reported in several conditions 1-3 other than pheochromocytoma. A response considered diagnostic of pheochromocytoma in a patient with a recent cerebral hemorrhage was reported by Ross in 1954.4 We have been impressed with the frequency of this "false-positive" reaction and therefore have tested a group of randomly selected patients with recent cerebrovascular accidents to assess the incidence of blood pressure response to phentolamine meeting the criteria set out as highly suggestive of pheochromocytoma.1,2 MATERIALS AND METHODS Twelve patients with the recent onset of cerebrovascular disease were studied to evaluate their response to phentolamine. No drugs had been taken for at least 48 hours prior to the test. Duration of hypertension and history of previous cerebrovascular accidents were recorded (Table 1).Left ventricular hypertrophy (LVH) was graded on physical examination by the distance of the apical heave from the midsternal line (SL):