Clarithromycin is a relatively new macrolide antibiotic that to our knowledge has not previously been associated with pancreatitis. The older macrolide, erythromycin, is a well-established drug known to cause pancreatitis [1, 2]. We report the first case of clarithromycin-induced pancreatitis.

A 58-year-old healthy woman reported dry cough persisting for 1 month without fever. Results of a physical examination were unremarkable. Chest radiography showed diffuse interstitial markings in the lungs. The working diagnosis was atypical pulmonary infection, and clarithromycin was begun at a dosage of 500 mg twice daily. Five days after treatment began, the patient reported severe vomiting, nausea, and mild epigastric pain and was referred to our hospital. On admission, the results of physical examination were normal except for mild epigastric tenderness. Laboratory findings showed hyperamylasemia (amylase level, 1200 IU/mL; normal range, 150 to 400 IU/mL) and hyperlipasemia (lipase level, 80 IU/mL; normal range, 4 to 33 IU/mL). The patient was hospitalized for observation, and clarithromycin therapy was discontinued. After 3 days of conservative treatment, symptoms resolved and amylase and lipase levels returned to normal. Ultrasonography of the abdomen showed no cholelithiasis, dilatation of the choledecus, or pancreatic abnormality. The patient was not alcoholic, and no causes for her pancreatitis other than clarithromycin could be determined.

Clarithromycin is emerging as a commonly used antibiotic for respiratory infections. Clinicians should be aware of this serious side effect of the drug.