Anti-obesity medication

What counts as an anti-obesity medication?

NIDDK calls prescription anti-obesity drugs weight management medications; some work by helping a person feel less hungry or full sooner, while others make it harder for the body to absorb fat from food [1]. NIDDK's June 2024 list of long-term options includes orlistat, phentermine-topiramate, naltrexone-bupropion, liraglutide, semaglutide (sold as Wegovy), and tirzepatide (sold as Zepbound); setmelanotide is used only for specific rare genetic disorders [1]. Wegovy is now also approved as a tablet, for adults with obesity or with overweight and at least one weight-related condition [2]. Foundayo (orforglipron), an oral GLP-1 tablet, was approved April 1, 2026 [3][4].

Who can be prescribed one, and how well do they work?

NIDDK lists eligibility as an adult with a BMI of 30 or greater, or 27 or greater plus a weight-related condition such as high blood pressure or type 2 diabetes [1]. These medications work best combined with a lifestyle program: on average, after 1 year, adults taking one lose 3% to 12% more of their starting weight than people in a lifestyle program alone, with most loss in the first 6 months [1]. If a person has not lost at least 5% of starting weight after 12 weeks on the full dose, a clinician will probably advise stopping, and NIDDK says people will probably regain some weight after stopping [1].