Semaglutide is the active ingredient inside Ozempic. Think of it the way you’d think of ibuprofen and Advil: one is the drug itself, the other is a brand name for a product built around that drug. Ozempic is one of several brand-name medications that contain semaglutide, each designed for a different medical purpose and sold at different doses.
How Semaglutide and Ozempic Relate
Semaglutide is a manufactured version of a hormone your small intestine naturally produces called GLP-1. This hormone does several things at once: it signals your pancreas to release insulin, slows down how quickly your stomach empties food, blocks a second hormone that raises blood sugar, and acts on areas of the brain involved in hunger and fullness. Semaglutide mimics all of these effects by binding to the same receptors the natural hormone uses.
Ozempic is the brand name Novo Nordisk gave to its injectable semaglutide product for type 2 diabetes. It’s FDA-approved specifically to improve blood sugar control in adults with type 2 diabetes, reduce the risk of major cardiovascular events (heart attack, stroke, cardiovascular death) in adults with type 2 diabetes and heart disease, and protect kidney function in adults with type 2 diabetes and chronic kidney disease. When people say “Ozempic,” they’re talking about this particular product with its particular dosing, pen device, and approved uses.
Other Brand Names for Semaglutide
Ozempic isn’t the only semaglutide product on the market. Wegovy contains the same active ingredient but is approved for a different set of conditions: weight management in adults and children 12 and older, treatment of a liver disease called MASH in adults with moderate or advanced scarring, and cardiovascular risk reduction in adults with obesity or overweight who also have heart disease. Wegovy also goes up to a higher maximum dose, 2.4 mg per week as an injection (and up to 25 mg as a pill), compared to Ozempic’s 2 mg maximum.
Then there’s Rybelsus, an oral semaglutide tablet you take once daily rather than injecting weekly. Rybelsus is prescribed for type 2 diabetes and comes in 7 mg and 14 mg daily tablets. Patients sometimes switch between the injectable and oral forms depending on preference and how well they tolerate each.
All three products deliver semaglutide to your body. The differences come down to the condition being treated, the dose, and how you take it.
What Ozempic Dosing Looks Like
Ozempic is a once-weekly injection you give yourself on the same day each week, at any time, with or without food. You start at 0.25 mg for the first four weeks, which is not yet a treatment dose. It’s just meant to let your body adjust. After that, your dose increases to 0.5 mg, and depending on your condition and response, your prescriber may continue increasing up to the 2 mg maximum. For people with type 2 diabetes and chronic kidney disease, the recommended maintenance dose is 1 mg.
This gradual ramp-up matters because semaglutide’s side effects are closely tied to how quickly the dose increases.
Side Effects to Expect
Digestive issues are by far the most common side effects with semaglutide, regardless of the brand name. In a large cross-sectional analysis of patients taking GLP-1 medications, abdominal pain was reported by 57.6% of users. About a third experienced diarrhea (32.7%) or constipation (30.4%), and roughly one in four reported nausea and vomiting (23.4%). Less common but more serious effects included gastroparesis (severely delayed stomach emptying) at 5.1% and pancreatitis at 3.4%.
These numbers reflect real-world reporting across GLP-1 medications broadly, not just Ozempic specifically. Most people find that nausea and stomach discomfort improve after the first few weeks at each dose level, which is why the slow titration schedule exists.
How Well It Works for Weight Loss
Although Ozempic is approved for diabetes rather than weight loss, semaglutide’s effect on appetite and fullness leads to significant weight reduction. In the STEP UP trial, participants taking 2.4 mg of semaglutide weekly lost an average of 15.6% of their body weight. A higher 7.2 mg dose (not yet widely available) produced an average loss of 18.7%, compared to 3.9% for placebo. These results are why semaglutide, under the Wegovy brand, became one of the most prescribed weight-loss medications in the country.
Compounded Semaglutide Is a Different Story
With demand for semaglutide surging, compounding pharmacies have begun selling their own versions. These are not the same as Ozempic, Wegovy, or Rybelsus. Compounded drugs are not reviewed by the FDA for safety, effectiveness, or quality before they reach consumers.
The FDA has flagged a specific concern: some compounded products use salt forms of semaglutide, such as semaglutide sodium or semaglutide acetate, rather than the base form used in approved medications. These are technically different active ingredients. The FDA has stated it has no information on whether these salt forms share the same chemical and pharmacologic properties as the semaglutide in Ozempic, and the agency is not aware of any lawful basis for using them in compounding. If you’re considering a compounded version, this distinction is worth understanding. A product labeled “semaglutide” from a compounding pharmacy may not behave the same way in your body as the FDA-approved version.