We present two cases of acute liver injury associated with sitagliptin. The first case was a 58-year-old male with a history of poorly controlled type 2 diabetes mellitus and hyperlipidemia. Sitagliptin was added for better control of diabetes. After initiation of sitagliptin, the patient's serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels increased gradually over a period of six months. The second case was a 44-year-old female with type 2 diabetes mellitus, and she experienced a more than ten-fold elevation in ALT and AST levels after starting sitagliptin therapy. Both patients did not have any history of alcohol abuse, acetaminophen use, or chronic liver disease. In the literature review, the reported magnitude of liver enzyme derangement with sitagliptin is generally mild and transient (two-fold upper limit of normal). We believed that the acute derangement of ALT and AST in our patients was due to sitagliptin since the ALT and AST normalized shortly after sitagliptin was discontinued and remained at baseline after resuming all other medications. Further research is needed to understand the mechanism of dipeptidyl peptidase 4 (DPP-4) inhibitors associated liver injury.
Keywords: drug-induced liver injury; side effects; sitagliptin; type 2 diabetes mellitus.