1mg Wegovy Compared to Mounjaro: What Changes at This Dose?

What does 1mg actually mean in the Wegovy titration schedule?

Wegovy follows a stepwise titration: 0.25mg, then 0.5mg, then 1mg, then 1.7mg, and finally the 2.4mg maintenance dose most people reach around week 17. The 1mg step exists to help your body adapt gradually rather than to deliver the full therapeutic effect. That context matters when you compare the two medicines, because Mounjaro's schedule runs on a separate track entirely: it begins at 2.5mg as a tolerability step, rising through 5, 7.5, 10, 12.5, and up to 15mg. If you'd like a fuller picture of how those ladders relate to one another, the Mounjaro-to-Wegovy dose conversion guide walks through each rung in detail.

The practical implication: someone taking 1mg semaglutide is still building towards their maintenance dose, whereas someone on Mounjaro 2.5mg is doing the same thing from the other medicine's starting point. Comparing the two at these early stages tells you relatively little about which will work better for you. Both are licensed for adults with a BMI of 30 or above, or 27 or above with at least one weight-related condition, and suitability rests on more than the number on the pen. If you are at the 0.5mg step and curious how it stacks up, our guide to 0.5mg Wegovy compared to Mounjaro covers that earlier stage in detail. The NHS medicines page for tirzepatide and semaglutide outlines the basics for each, and a prescriber will assess the whole picture before settling on a direction.

Do the two medicines work in the same way at comparable doses?

No, and the mechanism is the most important difference. Wegovy (semaglutide) is a GLP-1 receptor agonist, targeting a single gut-hormone pathway to reduce appetite and slow digestion. Mounjaro (tirzepatide) activates both GLP-1 and GIP receptors, which is why it is sometimes described as a dual-agonist. It is the only medicine of its kind licensed for weight management in the UK.

Whether that dual action translates into better results for any individual is not something a dose comparison resolves on its own. The SURMOUNT-5 head-to-head trial, published in the New England Journal of Medicine in 2025, found greater average weight reduction with tirzepatide over 72 weeks, but both medicines produced clinically meaningful losses and individuals respond differently. NICE's appraisal of tirzepatide, TA1026, notes that indirect comparisons favour tirzepatide while acknowledging the limitations of cross-trial analysis. The decision is never made on mechanism alone; your health history, how you tolerated earlier steps, and what your prescriber finds at clinical review all shape it.

It is worth keeping in mind that 1mg semaglutide is a transitional step. Our detailed breakdown of 1mg semaglutide versus Mounjaro explores the side-effect profiles at this stage, which do differ in character if not always in severity.

How do the trial results compare at maintenance, not at 1mg?

Because no head-to-head trial tested 1mg semaglutide against any Mounjaro dose, a fair comparison requires looking at what each medicine achieved at its licensed maintenance level. The table below draws on the pivotal UK trials.

Sources: STEP 1, NEJM; SURMOUNT-1, NEJM; MHRA approval of the 7.2mg Wegovy pen, April 2026. The 7.2mg figure narrows the gap considerably, and trial averages reflect populations, not individuals. You can also read about how Wegovy doses compare to Mounjaro across the full titration schedule if you want broader context beyond the maintenance figures. The Wegovy 2.4mg vs Mounjaro page goes deeper on the maintenance comparison if you are further along in treatment.

Which is right for you, and how does that decision get made?

If you are currently on 1mg Wegovy and wondering whether Mounjaro would serve you better, that is one of the questions our prescribers hear most often. The honest answer is that it depends on your response so far, your side-effect experience, your wider health profile, and your preferences. Both medicines carry a similar gastrointestinal side-effect character at early doses: nausea, loose stools, and reduced appetite are common to both, typically most noticeable after a dose step and usually settling within a couple of weeks. Neither medicine suits everyone.

Switching between treatments is a clinical decision, not a simple swap. A prescriber needs to see evidence of where you are in your current treatment, how you have tolerated it, and whether a switch is clinically appropriate. At nume, transfer patients go through the same thorough clinical review as those starting fresh, with a real prescriber reading every response before anything is approved or dispatched. Our FAQs cover the transfer process in plain language if you are weighing up your options.

There is no universally right answer between these two medicines. The right one is the one that fits your clinical picture, not a dose-by-dose chart. To explore your options properly, the starting point is a free consultation with our team at our weight-loss treatments page.