Wegovy 2.5mg: what the dose actually is and what to expect

Why 2.5mg keeps coming up, and where it actually belongs

This is one of the questions our prescribers field most weeks. The mix-up is understandable: Wegovy and Mounjaro are both once-weekly injections, both licensed for weight management, and both have a low "starter" dose that steps up over several months. But their numbers are completely different.

Mounjaro's opening dose is 2.5mg. Wegovy's is 0.25mg, a tenth of that. When someone reads about "starting on 2.5" in a forum or a social media post, there's no guarantee they know which medicine is being discussed. Searching for "Wegovy 2.5mg" is a completely natural mistake. The answer is just: that dose doesn't exist for Wegovy.

It's worth being precise about this because dose confusion with prescription medicines isn't trivial. If you were switching from Mounjaro to Wegovy, for instance, your prescriber would walk you through what the equivalent position on the Wegovy scale looks like for you, that's not something to guess at. You can read more about how the two medicines compare as licensed UK treatments if that context would help.

What the Wegovy dose ladder actually looks like

The licensed Wegovy injection schedule runs: 0.25mg, 0.5mg, 1.0mg, 1.7mg, and 2.4mg, each step held for roughly four weeks, though your prescriber sets the pace based on how you're tolerating each level. The full Wegovy dose schedule has more on how this works in practice.

The 0.25mg opening dose is a tolerability measure. Its job is to give your system time to adjust, particularly your gut, which responds strongly to GLP-1 receptor agonists in the early weeks. Nausea, loose stools and indigestion are common at the start; stepping up slowly keeps them manageable for most people. Your pen lives in the fridge (2–8°C), and checking the storage note on your Patient Information Leaflet is worth doing before you start, since there is a limited window for room-temperature use.

In April 2026, the MHRA approved a new 7.2mg single-dose pen for Wegovy, for adults with a BMI of 30 or above. This extended the maximum dose beyond the previous 2.4mg ceiling and brought Wegovy's ceiling results closer to those seen with higher-dose tirzepatide. If you're already established on treatment and wondering whether 7.2mg is a consideration for you, that's a conversation for your prescriber rather than a self-referral decision. If you are earlier in the titration journey, you can find out what to expect when you move up to the 0.5mg Wegovy dose, or read about how the 5mg Wegovy stage fits into the schedule before reaching maintenance. The 2.4mg Wegovy page covers what to expect at the maintenance stage.

Does it matter which medicine you're on, and who decides?

Both Wegovy and Mounjaro are licensed for adults with a BMI of 30 or above, or 27 or above alongside a weight-related condition such as high blood pressure, high cholesterol or obstructive sleep apnoea. That part of the eligibility picture overlaps. What differs is the mechanism (Wegovy targets one gut-hormone receptor; Mounjaro targets two), the dose schedule, the trial evidence, and the clinical considerations specific to you.

NICE's appraisal of tirzepatide (Mounjaro) found it produced greater average weight loss than semaglutide 2.4mg in a head-to-head trial, though NICE's guidance (TA1026) also notes that indirect comparisons carry limitations. The 7.2mg Wegovy data narrows that gap. But neither figure tells you which medicine suits your history, your other medicines, or your preference about injection versus how dose titration is handled. That is what the clinical consultation is for.

The decision is genuinely a clinical one. A prescriber reviews your answers (not software) and works through what the evidence means for you specifically. If you'd like an honest sense of what Wegovy costs privately in the UK, that information is available separately.

What 2.5mg would mean for Mounjaro, briefly

If you arrived here because you were actually asking about Mounjaro's 2.5mg starter dose, the short answer is the same principle applies: the first dose is a tolerability step, not a therapeutic target. Titration happens under prescriber oversight, and the final maintenance dose depends on your response and how you're getting on. The weight-loss treatments overview covers both medicines side by side if you're still deciding which to explore.

Whichever route feels right, speaking to a prescriber is the place to start. At nume, every consultation is reviewed by a GPhC-registered Independent Prescriber, the same working day. Speak to our prescribers if you'd like to take that step.