Lorcaserin is a novel and selective agonist of the 5-HT₂cR recently approved by the FDA for weight loss therapy. It acts selectively at this receptor subtype with minimal activation of 5-HT₂ᴀR or 5-HT₂ᴃR receptors. Based on initial clinical studies leading to its approval, lorcaserin is well tolerated and probably does not cause cardiac valve disease or other serious side effects. Even so, given the potential for serious adverse events, the FDA has limited its use to patients who are either obese or overweight with a medical complication such as hypertension. Whether or not lorcaserin will become generally accepted as a long-term treatment for obesity will depend on the results of ongoing post-marketing studies of cardiovascular outcome data.