Inhalation anesthetics, particularly the hydrocarbons and cyclopropane. lower the threshold to the arrhythmogenic activity of catecholamines. This interaction is of concern during the resection of a pheochromocytoma when the surgically-induced release of large amounts of norepinephrine and epinephrine from tumors sets the stage for ventricular arrhythmia by a direct effect on the myocardium together with an increase in blood pressure. In this communication, anesthesia was performed with N2,O-O2,-halothane. In addition patient was managed successfully, using d-tubocurarine, phentolamine (Regitine) and propranolol (Inderal). For the next same case, enflurane is recommended because of absence of flammability, arrhythmogenic activity and nephrotoxity. etc.