Background: Dipeptidyl peptidase (DPP)-4 inhibitors are commonly used agents to treat type 2 diabetes mellitus (T2DM). Although generally well tolerated, stomatitis has been previously reported as an adverse event with sitagliptin and linagliptin. Stomatitis with alogliptin has not been reported in post-marketing data to date. Objective: To report a case of suspected drug-induced stomatitis in a patient who received alogliptin for T2DM which resolved upon discontinuation of the offending agent. Summary: A 60-year-old male with T2DM began treatment with a DPP-4 inhibitor, alogliptin. After 4 doses of alogliptin, the patient reported inflammation and irritation along the lateral borders of his tongue, along with open fissures and oral ulcerations on the dorsal surface of the mucosa. He was subsequently diagnosed with stomatitis. Patient discontinued alogliptin and reported improvement in symptoms within 48 hours. Lesions re-epithelialized within 4 weeks after cessation of alogliptin. The Naranjo Algorithm was used to assess causality. The total score was 7, which when interpreted, implicates alogliptin as a "probable" cause of the reaction. Conclusion: A causality assessment determined alogliptin was a "probable" cause of stomatitis experienced by this patient. This adverse effect has not been reported with alogliptin to the authors' knowledge.
Keywords: adverse drug reaction; alogliptin; diabetes mellitus; oral ulceration; stomatitis.