"Wegovy vs Mounjaro" compares a weight-management drug with a diabetes drug. In the United States, Wegovy is semaglutide approved for weight reduction; Mounjaro is tirzepatide approved only for people with type 2 diabetes. Tirzepatide's US weight-loss brand is a third name, Zepbound. The search exists anyway because in the United Kingdom Mounjaro is licensed for weight management too, and the British pharmacy pages that answer it travel.
No trial has ever tested Mounjaro against Wegovy. What exists is a trial of the two molecules in obesity and a trial of the two molecules in diabetes, at different doses, in different people. This page sets out both, the two labels' indications and side-effect tables, and Wegovy's published prices. Labels were read on DailyMed and the UK electronic Medicines Compendium on 20 October 2026. Nothing here is a dose or a recommendation.
What each one is approved for
| Wegovy (semaglutide) | Mounjaro (tirzepatide) | |
|---|---|---|
| Maker | Novo Nordisk | Eli Lilly |
| US weight management | Yes — adults with obesity, or overweight with a weight-related condition; adolescents 12+ with obesity (injection) | No — tirzepatide's weight indication is on the Zepbound label |
| US type 2 diabetes | No (semaglutide's diabetes brands are Ozempic and Rybelsus) | Yes — blood-sugar control, adults and children 10+ |
| US cardiovascular risk reduction | Adults with established heart disease and obesity or overweight | Adults with type 2 diabetes at high cardiovascular risk |
| US liver disease (MASH) | Adults with F2–F3 fibrosis, accelerated approval (injection) | No |
| Forms | Weekly pen; daily tablet | Weekly injection, including the KwikPen |
| UK licence | Weight management | Type 2 diabetes and weight management |
US: WEGOVY prescribing information, SPL effective 18 June 2026 (version 19); MOUNJARO prescribing information, SPL effective 27 August 2026 (version 40). UK: Mounjaro KwikPen summary of product characteristics, text revised 29 August 2026. All read 20 October 2026.
Two consequences follow from the table. First, the cardiovascular claims are not the same claim: Wegovy's rests on SELECT, a trial in people without diabetes, and Mounjaro's on a trial in people with type 2 diabetes; Mounjaro vs Ozempic works through the same mismatch for the diabetes pair. Second, insurance follows the indication. A plan that covers diabetes drugs and excludes weight-loss drugs can cover Mounjaro and refuse Wegovy for the same person, and the reverse can happen to someone without diabetes; GLP-1 insurance coverage explains the rule. Using Mounjaro for weight loss in the US is off-label, which is set out on Mounjaro for weight loss.
Why British pages dominate this search
The UK Mounjaro licence, held by Eli Lilly, lists two indications: type 2 diabetes in adults, adolescents and children aged 10 and above, and weight management, including weight loss and weight maintenance, in adults with a BMI of 30 or more, or 27 to 30 with at least one weight-related condition such as high blood pressure, sleep apnoea, prediabetes or type 2 diabetes. In Britain, then, Wegovy and Mounjaro really are two weight-management injections, and pharmacies there sell both. That is the comparison the top search results answer. A reader in the United States asking the same question is comparing Wegovy with a diabetes brand, and the US-equivalent comparison is Zepbound vs Wegovy.
The two trials people actually mean
| SURMOUNT-5 | SURPASS-2 | |
|---|---|---|
| Who | 751 adults with obesity, no diabetes | 1,879 adults with type 2 diabetes on metformin |
| Tirzepatide given as | Zepbound, maximum tolerated 10 or 15 mg | Mounjaro 5, 10 or 15 mg |
| Semaglutide given as | 2.4 mg or maximum tolerated — Wegovy's dose | 1 mg — Ozempic's dose |
| Length | 72 weeks | 40 weeks |
| Weight result | -20.2% vs -13.7% | -7.6 / -9.3 / -11.2 kg vs -5.7 kg |
| Other result | Waist -18.4 cm vs -13.0 cm | HbA1c -2.0 / -2.2 / -2.3 vs -1.9 points |
SURMOUNT-5: Aronne et al., N Engl J Med 2025, least-squares mean percent change at week 72 as reported in the abstract. SURPASS-2: Mounjaro label, section 14, Table 5 (modified intent-to-treat population, least-squares means).
Neither trial is Mounjaro against Wegovy. SURMOUNT-5 is the weight-management comparison, but its tirzepatide arm is the Zepbound product and its people did not have diabetes. SURPASS-2 uses the Mounjaro brand, but compares it with semaglutide at less than half Wegovy's maintenance dose, and in people with diabetes, who lose less weight on every drug in this class. Putting the 11.2 kg from one beside the 20.2% from the other would mix two populations, two lengths and two units. Tirzepatide vs semaglutide covers both trials in full.
Wegovy has its own trial in people with diabetes, which is the closest thing to Mounjaro's population: in its 68-week STEP 2 study (Study 3 on the label), 807 adults with type 2 diabetes lost 9.6% of body weight on 2.4 mg against 3.4% on placebo. Wegovy's full trial record is on Wegovy weight loss results.
Side effects: two tables from two populations
| Adverse reaction | Wegovy 2.4 mg | Placebo | Mounjaro 5 / 10 / 15 mg | Placebo |
|---|---|---|---|---|
| Nausea | 44% | 16% | 12 / 15 / 18% | 4% |
| Diarrhoea | 30% | 16% | 12 / 13 / 17% | 9% |
| Vomiting | 24% | 6% | 5 / 5 / 9% | 2% |
| Constipation | 24% | 11% | 6 / 6 / 7% | 1% |
| Abdominal pain | 20% | 10% | 6 / 5 / 5% | 4% |
Wegovy: label Table 3, adults with obesity or overweight in 68-week weight-management trials (2,116 on Wegovy, 1,261 on placebo). Mounjaro: label Table 1, pool of placebo-controlled trials in adults with type 2 diabetes (about 240 per arm).
Read across, the table seems to say Wegovy causes roughly three times as much nausea. It does not establish that. The Wegovy figures come from long weight-management trials in people without diabetes in most arms; the Mounjaro figures come from shorter diabetes trials, and the placebo rates differ fourfold (16% against 4%), which is a sign of how different the trial conditions were. Tirzepatide's own weight-management label, Zepbound, reports nausea in 25%, 29% and 28% at the same three doses against 8% on placebo — about double the Mounjaro rates for the same molecule. The populations move the number more than the brand does. The like-for-like adverse-event comparison is SURMOUNT-5's, on the tirzepatide vs semaglutide page; each label in full is on Wegovy side effects and Mounjaro side effects.
Both labels carry the same boxed warning about thyroid C-cell tumours seen in rodents, and both list pancreatitis, gallbladder disease, kidney injury from dehydration and hypoglycaemia with insulin or sulfonylureas among their warnings.
What each costs without insurance
Novo Nordisk publishes Wegovy self-pay prices through its NovoCare pharmacy; read on 20 October 2026:
| Wegovy route | Self-pay price |
|---|---|
| Pen, 0.25 mg to 2.4 mg | $349 a month |
| Pen, 7.2 mg (Wegovy HD) | $399 a month |
| Pen, new patients, 0.25 mg and 0.5 mg | $199 for each of the first two months (offer through 31 December 2026) |
| Tablet, 1.5 mg | $149 a month |
| Tablet, 4 mg | $199 a month |
| Tablet, 9 mg and 25 mg | $299 a month |
| List price, pen, HD pen or tablet | $1,349.02 a package |
For Mounjaro, the published route is a savings card that requires commercial insurance and a prescription for an approved use, which in the US means type 2 diabetes; its two tiers are read term by term on the Mounjaro savings card page. Lilly's pricing pages refused unattended reads on 20 October 2026, so no Mounjaro figure is restated here; the dated figures are on Mounjaro cost, and Wegovy's history and conditions on Wegovy cost.
What this page does not answer
- Which one a particular person should use. That depends on whether they have diabetes, what their insurance covers, their history and their prescriber's judgement. This page reports the documents; it does not choose.
- A direct Mounjaro-against-Wegovy result. None exists, and the two trials above are not a substitute for one.
- How to move from one to the other. Neither US label describes it.
- UK prices. The UK licence is reported here because it explains the search; UK pharmacy prices are outside this site's US scope.
Sources
- Novo Nordisk, WEGOVY (semaglutide) injection and tablets, prescribing information, SPL effective 2026-06-18, version 19, DailyMed set ee06186f-2aa3-4990-a760-757579d8f77b: sections 1, 5, 6.1 (Table 3) and 14.2 — read 2026-10-20.
- Eli Lilly and Company, MOUNJARO (tirzepatide) prescribing information, SPL effective 2026-08-27, version 40, DailyMed set d2d7da5d-ad07-4228-955f-cf7e355c8cc0: sections 1, 6.1 (Table 1) and 14 (Table 5, SURPASS-2) — read 2026-10-20.
- Eli Lilly and Company, ZEPBOUND prescribing information, SPL effective 2026-08-28, version 40, DailyMed set 487cd7e7-434c-4925-99fa-aa80b1cc776b: Table 1 — read 2026-10-20.
- Eli Lilly Nederland B.V., Mounjaro KwikPen summary of product characteristics, section 4.1, date of revision 29 August 2026, electronic Medicines Compendium — read 2026-10-20.
- Aronne LJ et al. "Tirzepatide as Compared with Semaglutide for the Treatment of Obesity." N Engl J Med 2025;393:26-36 (SURMOUNT-5), PubMed 40353578.
- NovoCare Pharmacy, Wegovy pricing page — read 2026-10-20.