Along with diet, exercise, and behavior modification, drug therapy may be a helpful component of treatment for patients who are overweight or obese. In this review, I describe the new FDA-approved anti-obesity drugs and briefly introduce other anti-obesity drugs still under development. A variety of drugs for obesity have been developed and are regularly prescribed. Medications such as orlistat, phentermine, diethylpropion, phendimetrazine, and mazindol have been approved prior to 2011. New anti-obesity drugs such as lorcaserin (a selective 5-HT2C receptor agonist) and phentermine/topiramate were approved in 2012, and another two drugs, naltrexone/bupropion and liraglutide, were approved by the FDA in 2014. In Korea, orlistat and lorcaserin are permitted for long-time drug therapy for obesity, however naltrexone/bupropion and liraglutide have not been approved by KFDA yet. Medications are an important part for weight-loss therapy, but anti-obesity drugs can have serious side effects. Therefore the decision to initiate obesity drug therapy should be made only after a careful evaluation of the risks and benefits associated with long-term medication.