What Is Semaglutide? A Complete Guide to Ozempic, Wegovy & How They Work

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist, a class of medications that mimic the natural hormone GLP-1 produced in your gut. Originally developed by Novo Nordisk for type 2 diabetes, semaglutide gained widespread attention after clinical trials demonstrated significant weight loss results.

The medication is available under several brand names. Ozempic is FDA-approved for type 2 diabetes management and is administered as a weekly subcutaneous injection in doses up to 2 mg. Wegovy is specifically approved for chronic weight management at a higher dose of 2.4 mg per week. Rybelsus is the oral tablet form, approved for type 2 diabetes.

Semaglutide received its first FDA approval in 2017 for diabetes (Ozempic) and was approved for weight management (Wegovy) in June 2021. Since then, it has become one of the most prescribed medications in the United States, with millions of patients benefiting from its dual effects on blood sugar control and weight reduction.

Semaglutide works by binding to GLP-1 receptors throughout the body, triggering several biological responses that contribute to weight loss and improved metabolic health. The primary mechanism involves slowing gastric emptying, which means food stays in your stomach longer. This creates a prolonged feeling of fullness after meals.

In the brain, semaglutide acts on appetite centers in the hypothalamus, reducing hunger signals and cravings. Many patients report a dramatic decrease in food noise — the constant mental preoccupation with food that often drives overeating. This neurological effect is one of the key reasons semaglutide produces more consistent weight loss than diet and exercise alone.

For patients with type 2 diabetes, semaglutide also stimulates insulin secretion from the pancreas in a glucose-dependent manner. This means it helps lower blood sugar when levels are elevated, but does not cause dangerous drops in blood sugar (hypoglycemia) when levels are normal. It also suppresses glucagon, a hormone that raises blood sugar.

The STEP clinical trial program, which included over 10,000 participants, established semaglutide as a highly effective weight loss medication. In the STEP 1 trial, participants receiving semaglutide 2.4 mg lost an average of 14.9% of their body weight over 68 weeks, compared to 2.4% in the placebo group. Some participants lost more than 20% of their starting weight.

Beyond weight loss, the SELECT cardiovascular outcomes trial demonstrated a 20% reduction in major adverse cardiovascular events (heart attack, stroke, or cardiovascular death) among overweight or obese adults with established cardiovascular disease. This landmark finding led to an expanded FDA indication for cardiovascular risk reduction.

Patients with type 2 diabetes typically see A1C reductions of 1.0 to 1.8 percentage points, often bringing blood sugar levels into a well-controlled range. Many patients are able to reduce or eliminate other diabetes medications after starting semaglutide.

Semaglutide treatment follows a gradual dose escalation schedule to minimize gastrointestinal side effects. For weight management (Wegovy), the schedule begins at 0.25 mg weekly for the first four weeks, then increases to 0.5 mg, 1.0 mg, 1.7 mg, and finally the maintenance dose of 2.4 mg. The full escalation takes approximately 16 to 20 weeks.

The injection is administered once weekly using a prefilled pen, typically in the abdomen, thigh, or upper arm. Most patients find the injection simple and relatively painless, as the needle is very fine. The injection can be given on any day of the week, but it should be the same day each week.

Most patients begin noticing reduced appetite within the first one to two weeks. Meaningful weight loss — typically 5% or more of body weight — is usually observed within the first three months. Maximum weight loss typically occurs between 12 and 18 months of treatment. Patients should combine semaglutide with a reduced-calorie diet and increased physical activity for best results.

The retail price of brand-name semaglutide (Wegovy) is approximately $1,350 per month without insurance. Ozempic, often prescribed off-label for weight loss, costs around $900 to $1,000 per month at retail. However, compounded semaglutide is available through licensed pharmacies at significantly lower prices, often ranging from $250 to $400 per month.

Insurance coverage for semaglutide varies widely. Many commercial insurance plans cover Ozempic for type 2 diabetes but may not cover Wegovy for weight management. Medicare Part D began covering anti-obesity medications in 2026 following legislative changes. Some employers are adding weight management medications to their benefit plans due to evidence of long-term cost savings from reduced obesity-related health complications.

At Weight Method, we offer semaglutide subscriptions starting at $297 per month, which includes the medication, medical supervision, and ongoing support. Our clinicians evaluate each patient to determine the appropriate medication and dosing plan.