Repaglinide is a new, short-acting, insulin-releasing agent recently approved for the monotherapy of type 2 diabetes mellitus, and in combination with metformin in patients failing repaglinide or metformin monotherapy. Repaglinide appears to trigger insulin release by regulating adenosine triphosphate-sensitive potassium channels on the surface of pancreatic beta cells, which in turn affect calcium influx, the principal mediator of insulin release. Repaglinide mainly affects postprandial plasma glucose concentrations. It reduces glycosylated hemoglobin concentrations by 1-2% U. The agent's short duration of action may lessen the risk of long-lasting hypoglycemia and of down-regulation of beta cell sensitivity (the latter promoting secondary drug failure), although data are sparse in this regard. Its major adverse effect is hypoglycemia. Its role in the therapy of type 2 diabetes is unclear at present, vis-à-vis its use instead of or in combination with other antidiabetic agents other than metformin. The need for multiple daily doses, based on its brief duration of action, may be a barrier to compliance.