Case summary A 78-year old man was given, after surgery, 1 g ertapenem every 24 h intravenously. His clinical evolution was favorable and on day 8 ertapenem was discontinued and the patient was put on a semi-solid diet. On day 9, abdominal distension was seen accompanied by epigastric pain. The laboratory tests on day 8 showed an altered pancreatic profile: amylase = 1823 U/l (normal value: 0-100); lipase = 8045 U/l (normal value: 0-60); C-reactive protein (CRP) = 16.09 mg/dl (normal value: 0-0.5). Full Blood Count (FBC) showed leukocytosis with an increase in neutrophils and eosinophils. The prior pancreatic parameters were normal without leukocytosis. The evolution of clinical symptoms after discontinuing ertapenem was rapid. Between days 11 and 16, the laboratory parameters returned to normal values; the eosinophilia persisted longer, decreasing between days 14 and 16. Conclusions clinicians should include monitoring the development of acute pancreatitis in the safety parameters in patients undergoing treatment with this carbapenem.