Obesity is fast becoming the major cause of premature death in the developed world. The rising prevalence of obesity and obesity-related comorbidities also elevates healthcare costs, and reduced quality of life. The National Institute of Clinical Excellence in the UK recommends pharmacotherapy, in conjunction with lifestyle modification, for obese individuals [i.e. body mass index (BMI) of 30 kg/m(2)] and for overweight persons with a BMI greater than 27 kg/m(2), accompanied by at least one comorbidity. However, the current pharmaceutical treatment available to combat this epidemic remains limited. We review the efficacy and pharmacology of the anti-obesity agents currently used in clinical practice as well as some of the potential agents in phase II and III trials.