A Common Medication with an Uncommon Adverse Event: A Case of Doxycycline-induced Pancreatitis

Drug-induced pancreatitis is a rare entity. The diagnostic criteria for drug-induced pancreatitis include the development of pancreatitis during drug therapy, elimination of all other possible causes, resolution with discontinuation of the offending drug, and reappearance on using the same drug. Several drugs have been implicated in having an association with pancreatitis. Tetracyclines are considered to be a Class I medication (medications implicated in greater than 20 reported cases of acute pancreatitis). However, there are very few reported cases of doxycycline-induced acute pancreatitis. We report the case of a 55-year old male who presented to the emergency department (ED) with three days of progressively severe and constant mid-epigastric abdominal pain. On evaluation, he was found to have elevated lipase levels. Computed tomography (CT) scan of his abdomen revealed findings consistent with pancreatitis without any evidence of gallstones or common bile duct dilation. He denied alcohol use, trauma, and insect bites or stings. His calcium and triglyceride levels were within normal limits. His blood cultures did not show any bacterial growth. He had recently been initiated on doxycycline for concerns of cellulitis and had begun to develop abdominal pain seven days after the initiation of doxycycline. He had completed his antibiotic course on the day of presentation to the ED. He had no other recent medication changes. He had subsequent improvement of symptoms off of the doxycycline and with supportive care. Given that all other causes of pancreatitis had been excluded and that he had been initiated on doxycycline prior to presentation, the etiology was attributed to being likely secondary to doxycycline use. Our case highlights the importance of reviewing outpatient medications by the hospital medicine team and awareness of rare triggers for acute pancreatitis.