Pharmacological management of obesity

Obesity is a major chronic health problem in adults. It is a complex, multifactorial disorder characterised by excess accumulation of adipose tissue. It is associated with a number of complications including cardiovascular disease, hypertension, type 2 diabetes, dyslipidaemia and cancer. A weight loss in the order of 5-10% is associated with clinically meaningful reductions with respect to all comorbidities. Diet and exercise has been the cornerstone of weight management therapy, but this approach has limitations, especially for weight maintenance. Previous drugs used in obesity had serious side effects including valvular heart disease. However, recent drugs like orlistat and sibutramine have been rigorously tested and proven safe. Orlistat, a lipase inhibitor, inhibits absorption of dietary fat by approximately 30%. Taken with a hypocaloric diet, it produces and maintains clinically meaningful weight loss. Sibutramine is a centrally-acting agent which enhances satiety and thermogenesis by inhibiting serotonin and noradrenaline re-uptake. It is appropriate for patients who are unable to lose weight by lifestyle modification.