H2-receptor blockers are widely used for therapy of peptic ulcer disease and gastroesophageal reflux disease. H2-receptor blockers infrequently cause adverse hepatic effects, and when they occur they are usually asymptomatic. There are several previous reports of liver injury related to ranitidine. Until now, only two cases of acute hepatitis associated with the use of famotidine were reported in the world. We report three cases of clinical hepatitis that followed administration of famotidine (2 cases) and ranitidine (1 case). First, a 54-year-old woman received famotidine, 40mg, daily for treatment of erosive gastritis. After 6 weeks of treatment with famotidine, jaundice and itching sense developed. Second, a 45-year-old man was hospitalized for jaundice. He had a long history of duodenal ulcer and had been intermittently treated with famotidine. He had 6 weeks of treatment with famotidine prior to admission. Third, a 19-year-old woman was hospitalized for nausea, vomiting and urticaria. She had a history of acute hepatitis B virus infection and was discharged 4 weeks prior to readmission. She had been received ranitidine, 300 mg, daily for treatment of gastritis. After 17 days of drug ingestion, whenever she had taken her medication, she developed these symptoms of nausea, vomiting and urticaria. Other causes of hepatitis were ruled out and all patients recovered after discontinuation of drug ingestion. (Korean J Hepatd 1998;4:194 - 199)