Wegovy vs Mounjaro: which is better for weight loss?

Wegovy and Mounjaro aren’t a like-for-like pair. Wegovy is semaglutide from Novo Nordisk, approved for weight loss, while Mounjaro is tirzepatide from Eli Lilly, approved for type 2 diabetes. On the drugs inside them, tirzepatide produced more weight loss: in SURMOUNT-5, adults without diabetes lost 20.2% of their body weight on tirzepatide against 13.7% on semaglutide over 72 weeks.

If you want tirzepatide for weight loss, the approved product is Zepbound, which is also cheaper than Mounjaro self-pay. Wegovy costs less than either. Here is the comparison, with all three where it matters and prices as of October 27, 2026.

Wegovy, Mounjaro and Zepbound at a glance

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Sources: the Wegovy, Mounjaro and Zepbound labels, NovoCare, LillyDirect and the CMS Bridge form.

Tirzepatide vs semaglutide for weight loss: SURMOUNT-5

SURMOUNT-5 is the trial that tested the two molecules against each other for weight. It randomly assigned 751 adults with obesity but without type 2 diabetes to the highest dose they could tolerate of tirzepatide (10 or 15 mg) or semaglutide (1.7 or 2.4 mg, Wegovy’s maintenance doses), once a week for 72 weeks.

People on tirzepatide were also more likely to lose at least 10%, 15%, 20% and 25% of their weight. Stomach side effects were the most common in both groups, mostly mild to moderate and mostly while doses were rising. Two caveats: the trial was open-label, so people knew which drug they took, and Lilly funded it.

The tirzepatide in SURMOUNT-5 was given for weight, the way Zepbound is prescribed. Mounjaro’s own trials were in type 2 diabetes. The one that included semaglutide, SURPASS-2, compared tirzepatide 5 to 15 mg with semaglutide 1 mg over 40 weeks in 1,879 adults with type 2 diabetes: weight fell 7.6 kg to 11.2 kg on tirzepatide and 5.7 kg on semaglutide. Semaglutide 1 mg is an Ozempic dose, well below Wegovy’s 2.4 mg.

Each drug’s own trials

These are the label results against placebo. They come from separate trials with different volunteers, so compare each drug with its own placebo.

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Sources: Wegovy label, Tables 8 and 12; Zepbound label, Table 2. All figures count everyone assigned.

Two patterns stand out. People with type 2 diabetes lost less on both drugs, which matters if you have diabetes and are weighing Mounjaro against Wegovy. And Wegovy’s 7.2 mg dose, sold as Wegovy HD for adults who have tolerated 2.4 mg for at least 4 weeks, narrowed the gap: 18.8% over 72 weeks, between tirzepatide’s 10 mg and 15 mg results.

Why Zepbound, not Mounjaro, is Wegovy’s real rival

Mounjaro and Zepbound contain the same molecule at the same strengths, but only Zepbound is approved for weight reduction. That changes three practical things:

• The label. Prescribing Mounjaro for weight loss alone is off-label. Wegovy and Zepbound are both on label for it.
• The price. As of October 27, 2026, LillyDirect sells Zepbound vials and KwikPens at $299 for 2.5 mg, $399 for 5 mg and $449 from 7.5 mg when you refill within 45 days ($499 at 7.5 mg and $699 at 10 mg and up otherwise). Mounjaro is $499 at every dose.
• The savings card. Lilly’s Mounjaro card requires a prescription “for an approved use consistent with FDA approved product labeling,” which for Mounjaro means type 2 diabetes.

Never take Mounjaro and Zepbound together. When the FDA approved Zepbound, it said Zepbound should not be used with Mounjaro or a GLP-1 drug. Our Wegovy vs Zepbound guide is the like-for-like comparison, and Mounjaro vs Zepbound explains the two tirzepatide brands.

Side effects

All three labels carry a boxed warning for thyroid C-cell tumors. Semaglutide and tirzepatide caused these tumors in rodents, and it isn’t known whether they do in people. None of them is for anyone with a personal or family history of medullary thyroid carcinoma or MEN 2.

Stomach side effects come next on all three, mostly while the dose is rising. Rates are from each label’s placebo-controlled trials; compare each drug with its own placebo.

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In the weight trials, 6.8% of people on Wegovy 2.4 mg stopped because of side effects, against 3.2% on placebo, and 4.8% to 6.7% on Zepbound, against 3.4%. All three labels also warn about pancreatitis, gallbladder disease, low blood sugar, kidney injury from dehydration and severe stomach problems. See our GLP-1 side effects guide.

Doses and devices

Wegovy starts at 0.25 mg a week and steps up every 4 weeks through 0.5, 1 and 1.7 mg to the 2.4 mg maintenance dose from week 17, with 7.2 mg an option for some adults. It also comes as a daily pill, taken in the morning on an empty stomach with up to 4 ounces of water.

Mounjaro starts at 2.5 mg a week and rises in 2.5 mg steps at least 4 weeks apart, up to 15 mg, if blood sugar needs more control. Zepbound follows the same steps for weight, to a maintenance dose of 5, 10 or 15 mg.

What each costs in October 2026

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Prices read on October 27, 2026, from NovoCare, LillyDirect Mounjaro and LillyDirect Zepbound. Wegovy’s $199 new-patient offer runs through December 31, 2026. Wegovy HD (7.2 mg) costs $399 a month, and the Wegovy pill $149 to $299. With commercial coverage, both makers’ savings cards can bring a covered fill to as little as $25. Our Wegovy cost and Mounjaro cost guides go dose by dose.

Compounded tirzepatide costs less at many online programs: taking each program’s lowest ongoing monthly price, all in, at the 21 of the 26 programs we rank that publish one, compounded tirzepatide runs $85.58 to $378.08 a month, as of November 2026. It is not Mounjaro or Zepbound and not a generic of either. A compounding pharmacy prepares it, it isn’t FDA-approved, and the FDA doesn’t review compounded drugs for safety, effectiveness or quality before they’re sold. See our compounded tirzepatide rankings and compounded tirzepatide vs Zepbound.

Insurance and Medicare

Coverage follows the approved use. A commercial plan may cover Mounjaro for type 2 diabetes and exclude weight-loss drugs such as Wegovy and Zepbound, or the reverse, so check your plan’s drug list for the reason you’re being prescribed. Our insurance guide lists the questions to ask.

On Medicare, the GLP-1 Bridge charges eligible Part D enrollees $50 a month from July 1, 2026 to December 31, 2027, for weight-loss prescriptions. Its form lists Wegovy injections and tablets, Foundayo and the Zepbound KwikPen, not Mounjaro. Type 2 diabetes and heart-risk prescriptions go to your regular Part D plan. See does Medicare cover Wegovy or Zepbound.

Which one fits you

• If weight loss is the goal, Wegovy and Zepbound are approved for it; Mounjaro isn’t.
• For the largest average weight loss, tirzepatide led semaglutide in SURMOUNT-5. For weight, ask about Zepbound rather than Mounjaro.
• For the lowest cash price, Wegovy is $150 a month less than Mounjaro at maintenance, and the pill tops out at $299.
• With established heart disease and obesity or overweight, Wegovy carries the heart-risk indication.
• With type 2 diabetes and blood sugar as the main goal, your clinician may prescribe Mounjaro, which is approved for it from age 10.
• If you’re 12 to 17 without diabetes, Wegovy is approved for teens with obesity.

A licensed clinician can weigh these with your history, other medicines and coverage. Our brand-name GLP-1 rankings and semaglutide rankings compare programs that prescribe the approved brands, or try our match tool.

The bottom line

Wegovy is a weight-loss drug and Mounjaro a type 2 diabetes drug. Tirzepatide, the drug in Mounjaro, produced more weight loss than semaglutide in SURMOUNT-5, 20.2% against 13.7% over 72 weeks, but its weight-loss version is Zepbound, at $299 to $449 a month with refills within 45 days. Wegovy costs $349 a month after two $199 starter fills, comes as a pill and is approved to lower heart risk. Mounjaro is $499 self-pay as of October 27, 2026. Choose with a licensed clinician, and see our weight-loss hub for more.