Wegovy is the only semaglutide product FDA-approved for weight loss. It was approved in June 2021 for chronic weight management in adults, and later expanded to include children aged 12 and older. While other semaglutide brands exist, they are approved for different purposes.
What Wegovy Is Approved For
Wegovy is a once-weekly injection approved as an add-on to a reduced-calorie diet and increased physical activity for chronic weight management. To qualify, you need a BMI of 30 or greater (obesity), or a BMI of 27 or greater (overweight) with at least one weight-related health condition such as high blood pressure, type 2 diabetes, or high cholesterol.
The approval also covers adolescents aged 12 and older with obesity. This makes Wegovy one of relatively few prescription weight-loss medications available for younger patients.
How Wegovy Differs From Ozempic and Rybelsus
Three brand-name semaglutide products are on the market, and they’re often confused. Here’s what separates them:
- Wegovy (injection): approved for chronic weight management. Maintenance dose is 2.4 mg once weekly.
- Ozempic (injection): approved for type 2 diabetes. Maximum dose is 2 mg once weekly.
- Rybelsus (oral tablet): approved for type 2 diabetes and cardiovascular risk reduction. Not approved for weight loss.
All three contain semaglutide, but the doses and approved uses differ. Ozempic is frequently prescribed off-label for weight loss, meaning doctors use it for a purpose the FDA hasn’t formally approved. This happens partly because of Wegovy’s ongoing supply shortages and partly because some insurance plans cover Ozempic but not Wegovy. When doctors prescribe Ozempic off-label, they determine the dosage individually since the manufacturer doesn’t provide weight-loss-specific dosing guidance.
The key difference between Wegovy and Ozempic for weight loss comes down to dose. Wegovy’s maintenance dose of 2.4 mg is higher than Ozempic’s maximum of 2 mg, and Wegovy was specifically studied in clinical trials focused on weight management.
How Well It Works
In the landmark STEP 1 clinical trial, participants without type 2 diabetes who took Wegovy at the 2.4 mg dose lost an average of 14.9% of their body weight over 68 weeks (about 16 months). The placebo group lost just 2.4%. For someone starting at 250 pounds, that difference translates to roughly 37 pounds versus 6 pounds.
Real-world results tend to vary more than clinical trial outcomes, since trial participants receive close monitoring and structured support. Still, these numbers represent some of the strongest weight-loss results ever seen in a medication trial, which is a major reason semaglutide has drawn so much attention.
How the Dosing Works
You don’t start at the full dose. Wegovy follows a gradual five-step schedule, increasing every four weeks to give your body time to adjust. You begin at 0.25 mg per week and work your way up over about 16 to 20 weeks. The recommended maintenance dose is 2.4 mg once weekly, though some people stay at 1.7 mg if the higher dose causes too many side effects.
This slow ramp-up is specifically designed to reduce gastrointestinal problems, which are the most common reason people struggle with the medication early on.
How Semaglutide Causes Weight Loss
Semaglutide mimics a natural hormone called GLP-1 that your gut releases after eating. It works on two fronts. In the brain, it acts on areas that control appetite and satiety, reducing hunger signals and helping you feel full sooner. In the digestive system, it slows how quickly food leaves your stomach, which keeps you feeling satisfied longer after meals. It also helps regulate blood sugar by boosting insulin release and dialing back glucagon, a hormone that raises blood sugar.
The net effect is that most people simply eat less without feeling like they’re constantly fighting hunger. This is what distinguishes semaglutide from older weight-loss medications that relied more on stimulant effects or fat absorption blocking.
Common Side Effects
Gastrointestinal side effects are by far the most frequent issue. In pooled data from clinical trials, about 44% of people taking Wegovy experienced nausea, compared to 16% on placebo. Diarrhea affected around 30%, vomiting about 25%, and constipation roughly 24%. These symptoms are typically worst during the dose-escalation phase and tend to improve over time as your body adjusts.
Most side effects are mild to moderate, but they’re a real factor in whether people stick with treatment. The gradual dose increases help, and eating smaller meals can also make a noticeable difference.
Who Should Not Take It
Wegovy is not safe for everyone. You should not use it if you or a family member have had a type of thyroid cancer called medullary thyroid carcinoma, or if you have a condition called Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). A history of pancreatitis, serious bowel conditions, or depression with suicidal thoughts may also rule it out. Your prescriber will review your medical history before starting treatment.