Repaglinide-associated Atrial Fibrillation in the Elderly: A Case Report with Pharmacovigilance Implications

Abstract

Repaglinide, a meglitinide-class oral antihyperglycemic agent, is widely used for postprandial glycemic control in type 2 diabetes mellitus. Drug-induced atrial fibrillation (AF) is an underrecognized adverse drug reaction (ADR) with potentially serious hemodynamic consequences. We report a 70-year-old woman with type 2 diabetes who developed new-onset AF with rapid ventricular response (heart rate 148 bpm) and ST-segment depression (V3–V6) within 6 weeks of initiating repaglinide 2 mg thrice daily, prescribed after an episode of hypoglycemia on glimepiride. A thorough evaluation excluded structural heart disease, thyroid dysfunction, electrolyte disturbances, and other precipitants. Repaglinide was discontinued, rate control was achieved with intravenous diltiazem, and the patient converted to sinus rhythm within 48 h. Naranjo causality assessment yielded a score of 3 (possible), reflecting the contribution of age, diabetes, prior hypoglycemia, and a possible pharmacokinetic interaction with co-administered amlodipine. VigiBase records only 8 spontaneous reports of this ADR, and no published case report exists in the indexed literature to date. This case draws attention to repaglinide as a potential, though rare, trigger of AF and highlights the importance of considering drug–drug interactions and hypoglycemia-related vulnerability when initiating insulin secretagogues in elderly patients.