Amyotrophic lateral sclerosis with hypertensive attacks: Blood pressure changes in response to drug administration

Blood pressure changes in response to intravenous drug administration were examined in a respirator-dependent 49-year-old patient with sporadic amyotrophic lateral sclerosis (ALS) who developed severe hypertensive attacks. She showed severe hypertension and tachycardia during the daytime and nocturnal hypotension without compensatory tachycardia, which were consistent with the autonomic phenomenon reported in ALS patients. Infusion of phentolamine (2.5 mg) induced an abrupt 90 mmHg decrease in systolic pressure and slight increase in heart rate. Propranolol (1 mg) infusion induced decreases in both systolic pressure (36 mmHg) and heart rate (17 beats/min), although the pressure decrease was transient while the heart rate remained at the decreased level. Infusion of diazepam (10 mg) induced a 47 mmHg decrease in systolic pressure and a 23 beats/min increase in heart rate. These vasomotor responses indicate the distinct participation of abnormally augmented sympathetic tone, and especially of -sympathetic hyperactivity rather than of -sympathetic hyperactivity, in the hypertensive attacks occurring in this ALS patient.