Ozempic vs Semaglutide

Key differences

A product versus an ingredient

Semaglutide is what is inside the pen; Ozempic is the pen, the formulation and the label. Three US brands contain semaglutide: Ozempic, Rybelsus and Wegovy.¹³⁵ Ozempic's label is limited to adults with type 2 diabetes. It covers blood sugar control, lowering major cardiovascular event risk in those with established cardiovascular disease (added January 16, 2020), and lowering kidney decline, kidney failure and cardiovascular death risk in those with chronic kidney disease (added January 28, 2025).¹² Weight loss is not one of its approved uses.¹ FDA also approved the 2 mg weekly dose on March 28, 2022.²

What Ozempic adds to semaglutide

The ingredient has a fixed chemistry. The label gives the formula C187H291N45O59 and a molecular weight of 4113.58 g/mol.¹ PubChem files it as CID 56843331, and its CAS registry number is 910463-68-2.¹²¹¹ Semaglutide shares 94% of its sequence with human GLP-1, its peptide backbone is made by yeast fermentation, and its half-life is about 1 week, mainly because it binds to albumin in the blood.¹ Steady blood levels take 4 to 5 weeks of weekly doses, and the drug stays in the blood for about 5 weeks after the last one.¹

The product adds everything around that molecule. Each mL of the pen solution also holds disodium phosphate dihydrate (1.42 mg), propylene glycol (14 mg) and phenol (5.5 mg) in water for injection, at a pH of about 7.4. The single-dose syringes use sodium chloride in place of the propylene glycol and phenol.¹ Ozempic arrives as a ready-made clear liquid with no mixing step, and its instructions say never to draw it out of the pen with a syringe.¹ The pens come in three sizes: the 2 mg per 3 mL pen gives 0.25 mg or 0.5 mg doses, the 4 mg pen gives 1 mg doses and the 8 mg pen gives 2 mg doses.¹

One brand name, two routes

Since January 30, 2026, the Ozempic name has covered a tablet too. FDA approved a supplement that renamed Rybelsus formulation R2 as Ozempic tablets, and the tablets sit on the Rybelsus application, NDA 213051.⁴¹³ Ozempic tablets come in 1.5, 4 and 9 mg, and Rybelsus in 3, 7 and 14 mg; the label says the two tablet brands are not interchangeable milligram for milligram.³ The tablet schedule starts at 1.5 mg a day for 30 days, a starter dose that does not control blood sugar, then 4 mg, with 4 or 9 mg from day 61.³ The label allows people on the 0.5 mg weekly injection to switch to tablets one week after their last shot, on the prescriber's decision.³

Semaglutide that is not Ozempic

Several kinds of product use the word semaglutide without being Ozempic. Counterfeit pens are one. FDA has found counterfeit Ozempic 1 mg in the US drug supply chain three times: it had seized thousands of units by December 2023, seized several hundred units from lot PAR0362 on April 9, 2025, and seized dozens more from lot PAR1229 in late 2025.⁶ FDA advises patients to get Ozempic only with a valid prescription through state-licensed pharmacies and to check the product for signs of counterfeiting before use.⁶

Compounded and research-labeled products are others. Compounded semaglutide is not FDA approved, and FDA does not review compounded drugs for safety, effectiveness or quality before they are marketed.⁷ FDA has also warned companies that illegally sold unapproved semaglutide falsely labeled "for research purposes" or "not for human consumption" directly to consumers for human use, with dosing instructions. It calls these products of unknown quality and urges consumers not to purchase them.⁷ The label facts on this page describe Ozempic as Novo Nordisk makes it, not any other semaglutide product.

Outside the United States

The brand map differs abroad. The European Commission authorized Ozempic across the EU on February 8, 2018, for adults whose type 2 diabetes is not satisfactorily controlled, either alone when metformin cannot be used or added to other diabetes medicines.⁹ On March 26, 2026, the EU gave a conditional authorization to Kayshild, a semaglutide injection for adults with non-cirrhotic MASH and moderate to advanced fibrosis.¹⁰ In the US, that liver use sits on the Wegovy label instead.⁵

Which page to read next

For the brand, read What is Ozempic?, Ozempic dosage and Ozempic side effects; pen handling is on Ozempic injection sites and pen use. For the molecule across all its brands, read What is Semaglutide?. Related pairs: Ozempic vs Wegovy, Ozempic vs Rybelsus and Rybelsus vs semaglutide. Every pair is on the GLP-1 comparisons page.