S4137 Beyond Nausea: A Case of Colonic Bowel Obstruction Linked to GLP-1 Agonist Use

Introduction: Glucagon-like peptide-1 (GLP-1) receptor agonists are commonly associated with gastrointestinal adverse effects, primarily including nausea, vomiting, and diarrhea as a result of its effects throughout the gastrointestinal (GI) tract as well as on central nervous system. These medications have also been associated with gastroparesis and pancreatitis. There have been case reports showing more severe GI complications, which can include ileus or bowel obstruction. Case Description: A 52-year-old woman with past medical history significant of overweight presented to the emergency department (ED) shortly after initiation of semaglutide. She had recently had 3 additional ED visits at an outside hospital within the week preceding admission, all for similar complaints of constipation and abdominal pain that did not improve with laxatives or enemas. She reported no bowel movements within the last week before admission since starting semaglutide. The patient was notably uncomfortable, with diffuse abdominal tenderness and firm stool palpable in the rectal vault. Computed tomography abdomen and pelvis revealed a massive amount of gas and stool in the colon with colonic dilation up to 10.5 cm at the cecum and mid-sigmoid colonic narrowing, findings suspicious for stool-related colitis with partial colonic obstruction at the level of the sigmoid colon. The patient underwent urgent sigmoidoscopy which revealed a fecal impaction at the level of the sigmoid colon which was completely obstructing the lumen. It was broken up piecemeal via cold snare and rat-tooth forceps. No intrinsic stricture was found; biopsies were obtained which returned with nonspecific inflammatory changes. She was administered laxatives with improvement in her bowel function. She was recommended to stop semaglutide injections indefinitely and discharged home. Discussion: This case describes what was likely a colonic ileus leading to severe fecal impaction and bowel obstruction that did not respond to laxatives or enemas and required urgent endoscopic breakup of the impaction and decompression of the dilated colon. There may be different risk profiles in patients taking GLP-1 agonists with a history of type 2 diabetes, as there is an increased baseline risk for these patients. Given the explosion in use of these medications in recent years with estimates of nearly 1 out of 8 Americans trialing this class of medication, it is important to be aware even of rare side effects that may occur that can be directly linked to their use.