Wegovy (Semaglutide): How It Works, Results & Cost

What is Wegovy?

Wegovy is the brand name Novo Nordisk uses for semaglutide when it's prescribed for weight management at the 2.4 mg dose. It's a GLP-1 receptor agonist — a once-weekly injection you give yourself under the skin (subcutaneously) of the abdomen, thigh or upper arm, using a single-dose prefilled pen.

Semaglutide mimics the natural gut hormone GLP-1, which the body releases after eating. By activating GLP-1 receptors in the pancreas, gut and brain, Wegovy lowers appetite, slows how fast the stomach empties, and reduces the "food noise" many people describe — the constant background pull toward eating. The result, for most people, is eating less without the same effort of willpower, which over months translates into meaningful weight loss.

Wegovy is not a quick fix or a short course. It's designed as an ongoing treatment for obesity as a chronic disease, used alongside a reduced-calorie diet and increased physical activity. For the broader mechanism of how these drugs drive weight loss, see our GLP-1 weight-loss guide.

Wegovy at a glance

What is Wegovy approved for?

Wegovy carries more than one FDA approval, and the distinction matters for both treatment and insurance coverage:

• Chronic weight management in adults with obesity (a body mass index of 30 or higher) or who are overweight (BMI of 27 or higher) and also have at least one weight-related condition such as high blood pressure, type 2 diabetes, or high cholesterol. It's used alongside a reduced-calorie diet and more physical activity.
• Adolescents aged 12 and older with obesity, making it one of the first GLP-1 drugs approved for weight management in this younger group.
• Cardiovascular risk reduction. In 2024, Wegovy was also approved to reduce the risk of major cardiovascular events — heart attack, stroke and cardiovascular death — in adults with established cardiovascular disease who also have obesity or overweight. This approval was based on the large SELECT trial, which showed roughly a 20% relative reduction in major cardiovascular events versus placebo.

That cardiovascular indication is significant: it positions Wegovy not just as a weight-loss drug but as a treatment that may directly lower the risk of life-threatening events in the right patients — and it can affect whether some insurers, including Medicare in certain situations, will cover it.

How does Wegovy work?

Semaglutide is a long-acting copy of the GLP-1 hormone. Your own GLP-1 is broken down within a minute or two of being released, but semaglutide is engineered to resist that breakdown and to bind to a blood protein (albumin), so a single weekly injection keeps working for days. Once active, it produces several coordinated effects:

• It reduces appetite by acting on receptors in the brain's appetite centers, lowering hunger and cravings.
• It slows gastric emptying, so food stays in your stomach longer and you feel full sooner and for longer after meals.
• It improves blood-sugar control by prompting glucose-dependent insulin release — which is the property that first made semaglutide a diabetes drug.

Because these effects build over time and depend on dose, Wegovy is started low and increased slowly. The full 2.4 mg dose is what delivers the weight-loss results seen in trials.

How much weight do people lose on Wegovy?

The headline figure comes from the pivotal STEP-1 trial (Wilding et al., New England Journal of Medicine, 2021). Adults with obesity or overweight, without diabetes, took Wegovy or placebo for 68 weeks alongside lifestyle counseling.

On average, participants taking Wegovy lost about 15% of their starting body weight — roughly 33 pounds for someone starting at 220 pounds — compared with about 2.4% on placebo. A meaningful share of people lost 20% or more, while a minority responded much less. These are averages, and individual results vary widely depending on biology, dose tolerance, and how consistently lifestyle changes are maintained.

One honest caveat: the weight loss depends on staying on the drug. In a separate withdrawal study, people who stopped semaglutide regained a large share of the weight they had lost over the following year. This is why clinicians frame Wegovy as a long-term treatment for a chronic condition rather than a temporary intervention.

Dosing and titration schedule

Wegovy is taken as a once-weekly injection on the same day each week, with or without food. To limit nausea and other gastrointestinal side effects, the dose is increased gradually over about 16 to 20 weeks until you reach the 2.4 mg maintenance dose. The standard schedule is:

The starting 0.25 mg dose isn't meant to cause weight loss — it simply lets your body adjust. If side effects are bothersome at any step, a clinician may keep you at a lower dose for longer before stepping up, or in some cases settle on a lower maintenance dose you tolerate better.

Wegovy vs. Ozempic: what's the difference?

This is the most common point of confusion, and the answer is simple at its core: Wegovy and Ozempic are the same active drug — semaglutide — both made by Novo Nordisk. The differences are in dose, branding and approved use.

Because Wegovy reaches a higher maximum dose and is specifically studied and branded for weight loss, it's the version a clinician will usually prescribe when the goal is weight management. Ozempic is sometimes used "off-label" for weight loss, but that affects insurance coverage and supply. We compare them in depth on our Ozempic guide and across the full lineup in the GLP-1 medications comparison.

Side effects and safety

The most common side effects of Wegovy are gastrointestinal: nausea, diarrhea, vomiting, constipation, abdominal pain, and indigestion. These are usually mild to moderate, tend to be worst right after a dose increase, and ease over time — which is exactly why the dose is titrated slowly. Staying well hydrated and eating smaller, lower-fat meals can help.

Like other drugs in its class, Wegovy carries important warnings:

• Boxed warning for thyroid C-cell tumors. Semaglutide caused thyroid C-cell tumors in rodents; it is contraindicated in people with a personal or family history of medullary thyroid carcinoma (MTC) or the genetic syndrome MEN 2.
• Pancreatitis. Inflammation of the pancreas has been reported; severe or persistent abdominal pain should be evaluated promptly.
• Gallbladder problems, including gallstones, can occur, partly because rapid weight loss itself raises that risk.
• Other cautions include possible kidney effects (often from dehydration due to vomiting), gallbladder disease, and not using it in pregnancy.

What does Wegovy cost?

Wegovy's list price in the United States runs to well over a thousand dollars a month before insurance, though what you actually pay depends heavily on coverage. Some commercial insurance plans cover it for weight management when eligibility criteria are met; many exclude weight-loss drugs entirely. Manufacturer savings programs and the cardiovascular indication can change the picture for some people.

Because coverage is the single biggest factor in real-world cost, it's worth checking your specific plan's formulary and prior-authorization rules. We break down pricing, savings cards, and insurance strategies in our GLP-1 cost and insurance guide.

The bottom line

Wegovy is semaglutide at a higher, weight-loss-specific dose — a once-weekly injection that helps most people eat less and lose a meaningful amount of weight, around 15% on average in trials, with growing evidence that it also protects the heart in people with established cardiovascular disease. It's the same molecule as Ozempic but reaches a higher dose and is approved and branded for weight management.

It's most useful to think of Wegovy as a long-term treatment for obesity rather than a temporary diet aid: the results depend on staying on it, and stopping tends to bring weight back. A good next step is comparing it to Ozempic, reviewing the full medication lineup, or understanding the side effects and costs before talking to a clinician.

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