Abstract
An 84-year-old man who was being treated for aseptic necrosis of the left femoral head was referred to our department for evaluation of epigastralgia, nausea and loss of appetite. Upper gastrointestinal endoscopy revealed duodenal ulcers on the anterior and posterior walls of the duodenal bulb. He was treated with omeprazole. About 8 weeks after the initiation of omeprazole therapy, he developed pain in both breasts. A physical examination revealed gynecomastia, which disappeared after administration of omeprazole was discontinued. Although the patient was positive for hepatitis C virus antibody, his liver function was fairly well preserved during his clinical course. Serum levels of luteinizing hormone, follicle stimulating hormone and human chorionic gonadotropin were elevated, and levels of testosterone and dehydroepiandrosterone-S were decreased. These hormonal abnormalities persisted even after discontinuance of omeprazole therapy, suggesting that they represented age-related hormonal changes. Our findings suggest that gynecomastia was induced by omeprazole.
