Obesity is a growing health problem in our society and its treatment has been challenging. In recent decades, several anti-obesity drugs have been withdrawn from the market because of reported and documented adverse effects. After years of interruption, the US Food and Drug Administration (FDA) has recently approved multiple new anti-obesity drugs. The majority of these medications are taken orally, and only one is administered subcutaneously. In this article, we review the efficacy, adverse effects, and mechanism of action of all 5 FDA-approved drugs.