Arthroplasty in patients with elevated body mass index results in increased rates of reoperation, instability, revision, and infection. Preoperative weight loss may reduce the complication rate associated with orthopaedic surgery. In addition to lifestyle modification, anti-obesity medications are available to help patients to reduce their preoperative weight. Currently, there are 6 U.S. Food and Drug Administration (FDA)-approved anti-obesity medications in the United States: phentermine, orlistat, phentermine with topiramate extended release (ER), lorcaserin, sustained release (SR) naltrexone with bupropion, and liraglutide. Anti-obesity medications potentially provide a new way to optimize patients before surgery and to ensure successful recovery postoperatively.