Is Semaglutide the Same as Mounjaro?

Step 1: understand what each medicine actually is

The confusion is understandable. Both Mounjaro and Wegovy belong to a family of medicines that mimic gut hormones involved in appetite regulation and blood-sugar control, and both are given as once-weekly subcutaneous injections. That similarity leads a lot of people to assume they must be the same drug under different brand names. They are not.

Mounjaro contains tirzepatide, made by Eli Lilly. Tirzepatide is a dual GIP and GLP-1 receptor agonist: it activates two distinct receptor pathways simultaneously. Wegovy contains semaglutide, made by Novo Nordisk, and is a GLP-1 receptor agonist only, activating a single pathway. The question of whether Mounjaro is semaglutide has a plain answer: no, it contains a different active ingredient with a broader mechanism of action. As the NHS tirzepatide page and the NHS semaglutide page both set out clearly, these are separate molecules.

Ozempic is also semaglutide, but it is licensed in the UK for type 2 diabetes management, not weight loss. It should not be treated as equivalent to Wegovy for weight-management purposes, and it is not available through nume.

Step 2: compare what the trial evidence actually shows

The clinical programmes for these two medicines ran on different timescales, at different doses, in different cohorts, so direct comparison requires care. The table below draws on published data and NICE's appraisal work.

The SURMOUNT-5 head-to-head is the most relevant evidence for the direct comparison: published in the New England Journal of Medicine in 2025, it randomised 751 adults with obesity to either tirzepatide or semaglutide 2.4mg for 72 weeks and found tirzepatide produced greater average weight loss. The NICE appraisal of tirzepatide (TA1026) also notes that indirect comparisons favour tirzepatide. Those numbers do not mean tirzepatide is right for every individual; they describe group averages in trial populations.

For a closer look at whether semaglutide performs as well as Mounjaro in the available evidence, that page works through the data in more detail.

Step 3: what the licensing difference means for you in practice

Both medicines are licensed for weight management in the UK in broadly similar populations. The practical differences sit in the NICE recommendations, which govern NHS access, and in the specific eligibility thresholds each carries.

NICE recommends tirzepatide (TA1026) for adults with a BMI of 35 or above plus at least one weight-related comorbidity such as high blood pressure, type 2 diabetes or obstructive sleep apnoea, with thresholds 2.5 kg/m² lower for certain ethnic backgrounds. NICE recommends semaglutide (TA875) only within specialist weight management services and for a maximum of two years. For a side-by-side on NHS access and private pricing, the Wegovy vs Mounjaro comparison covers both routes.

Privately, both require a prescription following a clinical assessment. Neither can be purchased over the counter. At nume, a GPhC-registered Independent Prescriber reviews every consultation personally. Which medicine is clinically appropriate depends on your health history, any other medicines you take, and how you respond to treatment. Cost differences between the two are a real consideration too, private prices vary by dose and provider.

One point worth clearing up: some readers arrive believing Wegovy and Mounjaro are simply two names for the same product. They share a delivery method and a weekly schedule, but the active ingredients, the receptor pathways and the trial results are all distinct. That question is answered fully here.

If you are weighing up the options, a fuller side-by-side of Wegovy and Mounjaro may also help before you start your consultation. And if you want to understand the wider landscape of alternatives, this page on alternatives to Ozempic and Mounjaro covers the licensed options in the UK.

Which medicine suits you is a clinical decision our prescribers make with you, based on your individual picture.