Wegovy (semaglutide) is FDA-approved for weight loss, cardiovascular risk reduction, and the treatment of a serious liver condition called MASH. Most people associate it strictly with weight management, but its approved uses have expanded significantly since it first hit the market in 2021.
Weight Loss and Long-Term Weight Management
Wegovy’s primary use is reducing excess body weight and keeping it off long term. In the landmark STEP 1 clinical trial, adults taking semaglutide lost an average of 14.9% of their body weight over 68 weeks, compared to just 2.4% in the placebo group. For someone weighing 250 pounds, that translates to roughly 37 pounds lost.
The drug is approved for adults with obesity (a BMI of 30 or higher) and for adults with overweight (BMI of 27 to 29.9) who also have at least one weight-related health condition, such as high blood pressure, high cholesterol, or type 2 diabetes. It’s also approved for adolescents aged 12 and older with obesity. In all cases, it’s meant to be used alongside a reduced-calorie diet and increased physical activity, not as a standalone fix.
How It Works in Your Body
Wegovy mimics a natural hormone called GLP-1 that your gut releases after eating. This hormone acts on two key systems. First, it activates receptors in multiple areas of the brain’s appetite center, suppressing the neurons that drive hunger while boosting those that signal fullness. The net effect is that you feel satisfied sooner and think about food less between meals. Second, it slows the rate at which your stomach empties, so food stays in your digestive system longer and you feel full for an extended period after eating.
These dual effects on both the brain and the gut are what make semaglutide more effective than older weight-loss medications that targeted only one pathway.
Cardiovascular Risk Reduction
In March 2024, Wegovy became the first weight-loss medication also approved to reduce the risk of heart attack, stroke, and cardiovascular death. This approval applies specifically to adults who already have established heart disease and are living with obesity or overweight.
The evidence came from the SELECT trial, a large cardiovascular outcomes study. Participants taking semaglutide had a 20% lower rate of major cardiovascular events compared to those on placebo. Notably, this benefit appeared to go beyond what weight loss alone would explain. One analysis from NYU Langone found that semaglutide didn’t significantly change total cholesterol, LDL cholesterol, or blood pressure, suggesting the drug may protect the heart through other mechanisms, possibly by reducing inflammation in blood vessel walls.
Liver Disease (MASH)
Wegovy’s newest approved use is for the treatment of metabolic dysfunction-associated steatohepatitis, a progressive liver condition previously known as NASH. This isn’t the same as simply having a fatty liver. MASH involves active inflammation and scarring (fibrosis) of the liver, and it can eventually lead to cirrhosis or liver failure if untreated.
The approval covers adults with moderate to advanced liver fibrosis (stages F2 to F3) who have not yet developed cirrhosis. Before this, there were very few treatment options for MASH, making this a significant development for the estimated millions of Americans living with the condition, many of whom don’t know they have it.
Kidney Protection: Promising but Not Yet Approved
Semaglutide has also shown meaningful results for kidney health, though this is not yet an FDA-approved indication for Wegovy. In the FLOW trial, which studied people with type 2 diabetes and chronic kidney disease, semaglutide reduced the combined risk of major kidney events, cardiovascular events, and death from any cause by 24%. Major kidney events in that trial included significant loss of kidney function, kidney failure requiring dialysis or transplant, and kidney-related death. These results are notable because chronic kidney disease progresses irreversibly in many patients, and treatment options that slow that progression are limited.
What the Dosing Looks Like
Wegovy is a once-weekly injection given with a prefilled pen, typically in the abdomen, thigh, or upper arm. You don’t start at the full dose. Instead, you follow a gradual 16-week ramp-up schedule to reduce side effects, particularly nausea. The starting dose is 0.25 mg weekly for the first four weeks, then increases to 0.5 mg, then 1 mg, then 1.7 mg, with each step lasting four weeks. The maintenance dose for most adults is 2.4 mg per week, reached around week 17. An oral tablet form has also been approved for adults.
The pens should be stored in a refrigerator between 36°F and 46°F. If you need to keep one at room temperature (for travel, for instance), it stays usable for up to 28 days as long as the temperature doesn’t exceed 86°F. Freezing or heat exposure above 86°F renders the medication unsafe.
Common Side Effects
The most frequent side effects are gastrointestinal: nausea, diarrhea, vomiting, and constipation. These tend to be worst during the dose escalation phase and often improve once your body adjusts to the maintenance dose. The gradual titration schedule exists specifically to minimize these effects. Some people also report fatigue, headaches, or stomach pain. More serious but rare risks include pancreatitis and gallbladder problems, which are worth knowing about even though they affect a small percentage of users.