Cimetidine clearance and bioavailability in hepatic cirrhosis.

Nine patients with compensated alcoholic and nonalcoholic cirrhosis of the liver and 11 patients with peptic ulcer received 200 mg of cimetidine orally and intravenously. No differences were observed in cimetidine clearance between the group with peptic ulcer (556 +/- 44 ml/min, mean +/- SEM) and the group with cirrhosis (606 +/- 64 ml/min). The bioavailability of cimetidine was unchanged (84 +/- 4% and 97 +/- 7%). In the patients with cirrhosis, cimetidine clearance did not correlate with galactose elimination capacity or antipyrine clearance. Cimetidine clearance was related to creatinine clearance only when both groups were considered. A reduction of cimetidine dose in patients with compensated cirrhosis appears unwarranted.