Ozempic vs Wegovy vs Zepbound: Which GLP-1 Is Right for You?

What is each brand approved to treat?

The weight-management products are used with a reduced-calorie diet and increased physical activity [2]. Ozempic's label lists no weight-management indication; the semaglutide product approved for weight management is Wegovy [1][2].

Ozempic and Wegovy contain semaglutide, which activates the GLP-1 receptor. Semaglutide is a GLP-1 analogue with 94% homology to human GLP-1 and a half-life of about one week [2]. Tirzepatide activates both GIP and GLP-1 receptors [17].

Which produces more weight loss?

Where the two drugs have been compared directly, tirzepatide produced more weight loss. SURMOUNT-5 was an open-label trial that randomized 751 adults with obesity and no diabetes to the maximum tolerated dose of tirzepatide (10 or 15 mg) or semaglutide (1.7 or 2.4 mg) once weekly for 72 weeks. Mean weight change was -20.2% with tirzepatide and -13.7% with semaglutide, and waist circumference fell 18.4 cm versus 13.0 cm [4]. Gastrointestinal events were the most common adverse events in both groups and most were mild to moderate [4].

That comparison used semaglutide 1.7 or 2.4 mg. The Wegovy label now allows up to 7.2 mg weekly in adults who tolerate 2.4 mg for at least 4 weeks and need more weight loss [2]. In STEP UP, 1,407 adults with obesity and no diabetes received semaglutide 7.2 mg, 2.4 mg or placebo for 72 weeks; mean weight change was -18.7%, -15.6% and -3.9% [6]. Tirzepatide was not an arm of that trial.

Each drug also has its own large placebo-controlled trial. STEP 1 gave semaglutide 2.4 mg or placebo to 1,961 adults for 68 weeks and found weight changes of -14.9% versus -2.4% [7]. SURMOUNT-1 gave tirzepatide 5, 10 or 15 mg or placebo to 2,539 adults for 72 weeks and found -15.0%, -19.5% and -20.9% versus -3.1% [8]. These were separate trials, so their results are not a head-to-head comparison.

Does the health condition change the answer?

Type 2 diabetes

Ozempic's label covers glycemic control plus cardiovascular and kidney risk reduction [1]. In SUSTAIN-6, 3,297 adults with type 2 diabetes took semaglutide 0.5 or 1 mg or placebo for 104 weeks; cardiovascular death, non-fatal heart attack or non-fatal stroke occurred in 6.6% versus 8.9% (hazard ratio 0.74) [9]. In FLOW, 3,533 adults with type 2 diabetes and chronic kidney disease took semaglutide 1 mg or placebo, and the kidney composite outcome was 24% lower (331 versus 410 first events, hazard ratio 0.76) over a median 3.4 years [10].

Tirzepatide has also been compared with semaglutide in diabetes. In the open-label SURPASS-2 trial, 1,879 adults received tirzepatide 5, 10 or 15 mg or semaglutide 1 mg for 40 weeks, and HbA1c fell 2.01, 2.24 and 2.30 points versus 1.86 [3].

Cardiovascular disease without diabetes

SELECT enrolled 17,604 adults aged 45 or older with established cardiovascular disease and a BMI of 27 or higher, without diabetes. Semaglutide 2.4 mg reduced the composite of cardiovascular death, heart attack or stroke from 8.0% to 6.5% (hazard ratio 0.80) over a mean 39.8 months [11]. This is the trial behind Wegovy's cardiovascular indication [2].

MASH with fibrosis

Wegovy injection is approved for noncirrhotic MASH with moderate to advanced fibrosis (F2 to F3) under accelerated approval [2]. In the ESSENCE trial, an interim analysis at week 72 looked at the first 800 of 1,197 planned patients: MASH resolved without worsening fibrosis in 62.9% on semaglutide 2.4 mg versus 34.3% on placebo, and fibrosis improved without worsening MASH in 36.8% versus 22.4% [12].

Injection or tablet?

Wegovy comes as a weekly injection and as a daily tablet [2]. Ozempic comes as a weekly injection and, separately, as tablets approved for type 2 diabetes rather than weight management [1][13].

Wegovy tablets start at 1.5 mg for 30 days, then 4 mg for days 31 to 60, 9 mg for days 61 to 90, then 25 mg for maintenance. The label says to take one on an empty stomach in the morning with no more than 4 ounces of plain water, swallow it whole, and wait at least 30 minutes before food, drink or other oral medicines [2]. Oral bioavailability is about 1% to 2%, against 89% for the injection, so tablet and injection milligrams are not interchangeable [2].

Ozempic injection starts at 0.25 mg weekly for 4 weeks (not a maintenance dose), moves to 0.5 mg, and continues at 0.5, 1 or 2 mg, with 2 mg weekly as the maximum [1]. Wegovy injection steps up every 4 weeks from 0.25 mg to a recommended 2.4 mg, with 1.7 mg as an alternative maintenance dose and 7.2 mg as the maximum for adults who tolerate 2.4 mg and need more weight loss [2].

Side effects

Gastrointestinal effects are the most common problem with both drugs. In the pooled Wegovy 2.4 mg trials (2,116 adults on Wegovy versus 1,261 on placebo, up to 68 weeks), nausea occurred in 44% versus 16%, diarrhea in 30% versus 16%, vomiting in 24% versus 6% and constipation in 24% versus 11%; 6.8% on Wegovy stopped treatment for adverse reactions versus 3.2% on placebo [2]. In the pooled Ozempic diabetes trials (262 on placebo, 260 on 0.5 mg, 261 on 1 mg), any gastrointestinal reaction occurred in 15.3%, 32.7% and 36.4% respectively, and 0.4%, 3.1% and 3.8% stopped for gastrointestinal reasons [1]. Those sets come from different trials in different populations, and the labels caution that adverse reaction rates from separate trials are not directly comparable [2].

The Ozempic and Wegovy labels carry a boxed warning about thyroid C-cell tumors in rodents, with human relevance unknown, and both are contraindicated in people with a personal or family history of medullary thyroid carcinoma or MEN 2 [2][1]. Labeled warnings include acute pancreatitis, gallbladder disease, acute kidney injury from dehydration, hypoglycemia when combined with insulin or a sulfonylurea, severe gastrointestinal reactions (the drugs are not recommended in severe gastroparesis), hypersensitivity reactions, diabetic retinopathy complications in type 2 diabetes, and pulmonary aspiration during general anesthesia or deep sedation [2][1]. The labels do not state that semaglutide causes gastroparesis [2][1].

On pregnancy, the Wegovy and Ozempic labels advise discontinuing at least 2 months before a planned pregnancy, citing the long half-life of semaglutide [2][1].

What happens when you stop?

Weight regain is the consistent finding. In STEP 4, 803 adults who had lost weight during a 20-week run-in were randomized to continue semaglutide 2.4 mg or switch to placebo for 48 weeks; the continuing group lost a further 7.9% while the placebo group gained 6.9% [14]. In a one-year off-treatment extension of STEP 1, 327 participants regained 11.6 percentage points of the weight they had lost [15].

Matching the product to the indication

• If the diagnosis is type 2 diabetes, Ozempic's label covers glycemic control, cardiovascular risk reduction in established cardiovascular disease, and kidney outcomes in chronic kidney disease [1].
• If the goal is weight management, the approved semaglutide product is Wegovy and the approved tirzepatide product is Zepbound [2].
• If established cardiovascular disease without diabetes is part of the picture, Wegovy carries a cardiovascular risk-reduction indication based on SELECT [2][11].
• If MASH with F2 to F3 fibrosis is the reason for treatment, the Wegovy injection label covers it [2].
• If a daily tablet suits the routine better than a weekly injection, Wegovy tablets are the semaglutide tablet approved for weight management [2].

What about compounded semaglutide?

FDA says compounded drugs are not FDA approved and are not reviewed for safety, effectiveness or quality before marketing [16]. As of 2026-05-31 FDA had received 990 adverse event reports for compounded semaglutide [16].