• lorcaserin
• obesity

Obesity is developing into a pandemic in countries like the USA, the UK and India.1–3 The WHO projects that by 2015, about 700 million adults will be clinically obese.4 Obesity is a major public health problem, beyond the disability directly related to excessive adiposity, and it also increases the risk of several chronic diseases such as hypertension, sleep apnoea, diabetes, coronary artery disease and cancer. Clearly, obesity is a serious threat, imposing a vast economic burden on the healthcare system.5

Obesity is the second most common preventable cause of death, second only to tobacco use.6 Evidence suggests that weight reduction substantially lowers the risk of related comorbidities and fosters their therapeutic management.7 ,8 Although bariatric surgery has emerged as the most clinically effective strategy for decreasing body weight for people with morbid obesity (body mass index (BMI) ≥40) or for those who cannot be managed otherwise,9 it is a very invasive procedure with significant risks.10 ,11 At this juncture, behavioural therapy, lifestyle modification and pharmacotherapy remain the mainstays of treatment. The most appealing solution for the public in general would be a ‘weight loss pill’. Several drugs have been tested since the 1960s, such as thyroid hormone, dinitrophenol, various forms of amphetamines, aminorex, fenfluramine, phenylpropanolamine, rimonabant, orlistat and sibutramine. All but phentermine, phendimetrazine and orlistat have been banned because of serious side effects. Aminorex was introduced in 1965 in Switzerland and was found to cause pulmonary hypertension. Lorcaserin (ADP356; Trade name: Belviq marketed by Arena Pharmaceuticals) and topiramate/phentermine (Qsymia) are the most recent additions to the armamentarium of antiobesity medications.12

Lorcaserin is a novel drug acting selectively as a 5-HT_2C receptor agonist in the hypothalamus …