Exenatide Use in the Management of Type 2 Diabetes Mellitus

Exenatide is a GLP-1 (glucagon-like peptide-1) agonist that has been approved in the UK for use in the management of Type 2 Diabetes Mellitus (T2DM) since 2006. It acts by increasing glucose-induced insulin release and by reducing glucagon secretion postprandially. It therefore increases insulin secretion and reduces glucose levels, especially postprandially. It also reduces gastric emptying and acts centrally to promote satiety. In clinical practice it reduces HbA1c (range; -0.4% to -1.3%), fasting and postprandial blood glucose levels and is the only antidiabetic agent (together with liraglutide; a human GLP-1 analogue) to promote weight loss (range; -1.5 kg to -5.5 kg). It can be used as monotherapy or in combination with metformin and/or sulphonylureas (SU) and/or thiazolinediones (TZD). When compared with insulin it causes similar reductions in HbA1c and glucose levels, but unlike insulin it has the advantage of inducing weight loss. Its main side effect is gastrointestinal (GI) disturbances; nausea is the commonest GI adverse effect, albeit usually mild and transient. Hypoglycaemia is uncommon, especially when used as monotherapy or in combination with metformin. In this review article we scrutinize the currently available evidence for use of exenatide in the management of T2DM.