Propranolol increases arterial ammonia in liver cirrhosis.

Propranolol (20 mg 4 times a day) was given to patients with liver cirrhosis or fatty infiltration of the liver. In six patients with cirrhosis and a stable arterial plasma ammonia concentration before treatment, blood ammonia was increased significantly on day 3 of propranolol treatment. Arterial plasma ammonia concentration was still high on day 6 of propranolol. Individual percentage change in arterial ammonia ranged from 8% to 66%. After propranolol had been discontinued ammonia concentration returned to pretreatment concentrations in 3 to 6 days. In 3 patients with fatty livers and normal pretreatment ammonia concentrations no change was detected in arterial plasma ammonia while they were on propranolol.