INTRODUCTION: Obesity is a major health threat in the Western world because of its high incidence and prevalence, and its association with metabolic and cardiovascular disease as well as cancer. The reduction of food intake in obese patients can be achieved only transiently (generally for no longer than 6 months), in the absence of concomitant pharmacological therapy. Only bariatric surgery provides a means to increase satiety and/or decrease nutrient absorption in obese patients, in the long term. AREAS COVERED: This article reviews the available pharmacological treatments for obesity as well as the pharmacology and mechanism of action of exenatide in obese type 2 diabetic patients. EXPERT OPINION: Exenatide is a potential new candidate treatment for obesity, possibly in combination with other hormones that increase satiety (leptin) and slow gastric emptying (amylin).