Weight loss medications and what the FDA label actually says
A small number of medications are approved by the US Food and Drug Administration for chronic weight management. Several other medications are widely discussed in the context of weight loss without carrying an approval for it. The difference matters, and it is the first thing each page here states.
Every page in this category is built from the prescribing information that the manufacturer filed with the FDA. Approved uses, strengths, dosing, contraindications and the reported adverse reactions come straight from that document, and each page links to the exact label it was built from.
Nothing here is a recommendation. Which medication fits a particular person, if any, is a decision for that person and a licensed clinician.
Comparisons
- Ozempic vs WegovyOzempic and Wegovy both contain semaglutide but hold separate FDA approvals with different indications and maximum doses. Compared straight from both labels.
- Mounjaro vs ZepboundMounjaro and Zepbound are both tirzepatide from the same manufacturer, approved for different conditions. What each FDA label covers, side by side.
- Wegovy vs ZepboundWegovy and Zepbound are both approved by the FDA for chronic weight management but contain different active ingredients. What each label states, compared directly.
- Contrave vs QsymiaContrave and Qsymia are oral combination medications approved for chronic weight management. What each FDA label covers, including their different warnings.
Approved by the FDA for weight loss
Each of these has at least one FDA approval covering this use.
- SemaglutideFDA approved for this use
GLP-1 receptor agonist. Sold as Wegovy, Ozempic injection, Rybelsus and Ozempic tablets.
Semaglutide is sold in the United States under three brand names, and they are not interchangeable. Only Wegovy is approved for weight management. Ozempic and Rybelsus are approved for type 2 diabetes, and weight loss is not listed as an approved use in their labels.
- TirzepatideFDA approved for this use
GIP and GLP-1 receptor agonist. Sold as Zepbound, Mounjaro.
Tirzepatide is sold under two brand names with two different approvals. Zepbound is approved for weight management and for moderate to severe obstructive sleep apnoea in adults with obesity. Mounjaro is approved for type 2 diabetes. The active ingredient is identical.
- LiraglutideFDA approved for this use
GLP-1 receptor agonist. Sold as Saxenda, Victoza.
Liraglutide was the first GLP-1 receptor agonist approved for weight management. Saxenda carries that approval; Victoza, the same ingredient at lower maximum doses, is approved for type 2 diabetes. Both are injected once a day rather than once a week.
- Phentermine hydrochlorideFDA approved for this use
Sympathomimetic amine anorectic. Sold as Phentermine hydrochloride, Lomaira.
Phentermine is the oldest weight loss medication still in common use in the United States, approved in 1959. Its label differs from the newer medications in one important way: it is approved for short-term use, described in the label as a few weeks, and not for long-term treatment.
- Phentermine and topiramate extended-releaseFDA approved for this use
Combination anorectic and antiepileptic. Sold as Qsymia.
Qsymia combines phentermine with topiramate, a medication originally approved for seizures and migraine. Unlike phentermine on its own, this combination is approved for long-term weight management, and it is approved in adolescents aged 12 and older as well as adults.
- Naltrexone hydrochloride and bupropion hydrochlorideFDA approved for this use
Combination opioid antagonist and aminoketone antidepressant. Sold as Contrave.
Contrave combines naltrexone, used in opioid and alcohol dependence, with bupropion, an antidepressant also sold for smoking cessation. It is approved for long-term weight management and carries a boxed warning about suicidal thoughts and behaviours that comes from the bupropion component.
Lipase inhibitor. Sold as Xenical, Alli.
Orlistat is the only medication in this category that acts in the gut rather than on the brain or on hormone receptors. It is also the only one available without a prescription: Xenical is the 120 mg prescription capsule, Alli is the 60 mg over-the-counter version.
Discussed for this, but not approved for it
These medications are approved for something else. They are listed because people look for them here, and the honest answer is what the label covers.
- Metformin hydrochlorideNot approved for this use
Biguanide. Sold as Metformin hydrochloride.
Metformin is a first-line medication for type 2 diabetes and one of the most widely prescribed medicines in the world. It is often mentioned in discussions of weight, but its FDA label does not list weight loss among the approved uses, and no metformin product has been approved for it.