Stomach Pain Upon Stomach Pain: Medication-Induced Pancreatitis

As a first-line immunosuppressant to maintain remission in Crohn's disease, 6-mercaptopurine (6-MP) has been commonly used. A rare, unpredictable, dose-independent and idiosyncratic reaction to this medication is acute pancreatitis. Unlike other side effects of this drug which have been well characterized and are often dose-dependent, acute pancreatitis is an uncommon adverse effect not frequently encountered in clinical practice. In this case report, we describe a 40-year-old man with Crohn's disease who developed acute pancreatitis within two weeks of starting 6-MP. Discontinuation of the drug followed by fluid resuscitation led to the overall improvement of symptoms within 72 hours. No complications were noted during the follow-up. It is our intention to raise awareness for this lesser-known side effect with this case report and to urge physicians to provide thorough counseling prior to starting on this medication, especially in patients with inflammatory bowel disease (IBD). Additionally, we hope to reinforce this disease entity as a differential for acute pancreatitis and aim to emphasize the importance of detailed medication reconciliations with this report, especially in the emergency department, to enable quick diagnoses and limit unnecessary treatments.