Cimetidine hepatitis.

A 62-year-old man developed asymptomatic anicteric hepatitis during cimetidine therapy for duodenal ulcer disease. Liver biopsy revealed zonal (centrolobular) necrosis, bile stasis, and mononuclear cell infiltration. Electron microscopy featured mitochondrial hyperplasia, giant mitochondria, and liver cell bile inclusions. The diagnosis of cimetidine-related hepatitis was confirmed by re-exposure to cimetidine, which prompted a rapid rise in serum transaminases while under observation in the hospital. Cimetidine hepatitis is rarely reported, and routine monitoring of the patient's liver tests during therapy does not seem cost-effective as a general practice.