Mounjaro®
Starting from £179.99/mo
Start journey Learn moreHow the dose ladders differ, and what the trial data actually recorded
The dose schedules side by side
The table below sets out the licensed titration steps for each medicine. The figures come from the respective Summaries of Product Characteristics published on the eMC and are the same schedules UK prescribers follow.
| Stage | Mounjaro (tirzepatide) (weekly | Wegovy injection (semaglutide)) weekly |
|---|---|---|
| Starting dose | 2.5 mg | 0.25 mg |
| Step 2 (~4 weeks) | 5 mg | 0.5 mg |
| Step 3 (~4 weeks) | 7.5 mg | 1.0 mg |
| Step 4 (~4 weeks) | 10 mg | 1.7 mg |
| Step 5 (~4 weeks) | 12.5 mg | 2.4 mg (previous maintenance) |
| Maximum maintenance | 15 mg | 7.2 mg (approved by MHRA, April 2026) |
A quick check you can do right now: look at the pen in your fridge and confirm which rung of the ladder it represents, the strength is printed on the label and repeated in the Patient Information Leaflet. If the two don't match, call your pharmacy before injecting.
The titration pace matters as much as the target dose. Moving up too fast raises the chance of nausea and other gastrointestinal effects; moving up too slowly may delay the therapeutic benefit. That timing is set by your prescriber, not by the dose schedule alone, which is why questions about pace belong in your clinical review rather than in a dosing guide. If you'd like to compare Wegovy and Mounjaro doses across each titration step, that page goes into the practical differences in detail.
What the trial results recorded at each medicine's maximum dose
The SURMOUNT-1 trial (2,539 adults with obesity, 72 weeks, published in the New England Journal of Medicine) found that participants taking tirzepatide 15 mg lost around 20–21% of their body weight on average. The STEP 1 trial tested semaglutide 2.4 mg over 68 weeks in a similar population and recorded roughly 15% average weight loss, also published in the NEJM. Both figures are averages from controlled trials alongside lifestyle changes; individual results vary.
In 2025 the head-to-head SURMOUNT-5 trial, published in the New England Journal of Medicine, put tirzepatide directly against semaglutide 2.4 mg over 72 weeks and found tirzepatide produced greater average weight reduction. NICE's appraisal of tirzepatide (TA1026) references this indirect-comparison evidence in its recommendation.
The picture shifted further in April 2026 when the MHRA approved a dedicated 7.2 mg Wegovy pen, a higher maintenance dose than the previous 2.4 mg. Trials of the 7.2 mg dose reported around 20.7% average weight loss over 72 weeks, narrowing the gap with tirzepatide's top-end results considerably. If you want to understand exactly how those newer figures stack up, the page covering Wegovy doses compared to Mounjaro sets them out step by step alongside the equivalent tirzepatide data.
Why the milligram numbers are so different between the two medicines
Tirzepatide and semaglutide work through different receptors and have different molecular structures, so their active concentrations at clinical doses are not comparable by weight alone. Mounjaro activates two receptors (GIP and GLP-1) while Wegovy targets GLP-1 only. The higher milligram figures for tirzepatide simply reflect its pharmacology, not a stronger or more aggressive product. This is one of the most common misunderstandings our prescribers hear.
It also means that converting a Mounjaro dose to a Wegovy dose is not a straightforward arithmetic exercise. There is no universally accepted equivalence table, and clinical guidance does not endorse direct dose conversions. If you are switching between medicines, your prescriber will assess you afresh rather than map one number to another. The page on Mounjaro-to-Wegovy equivalent doses explains this in more detail, including what switching in practice involves.
For context on why the dose ceilings differ so significantly, this page on why Mounjaro's dose is higher than Wegovy's explains the receptor-level reasons without requiring a science background.
Which dose schedule is right for you
Eligibility for either medicine depends on your BMI, weight-related health conditions, other medicines you take and your full medical history, not the dose range alone. Under UK licensing, both medicines are indicated for adults with a BMI of 30 or above, or 27 or above with at least one weight-related condition. Lower BMI thresholds apply for some ethnic backgrounds under UK guidance. NICE's recommendations for tirzepatide set out the NHS criteria specifically.
The starting dose for both medicines is a tolerability step, its job is to help your body adjust, and the therapeutic effect builds as the dose increases. Whether 15 mg or 7.2 mg (or any intermediate rung) is the right ceiling for you depends on how you respond and what your prescriber judges appropriate. There is no clinical prize for reaching the highest dose; many people find an earlier step sufficient.
Costs also differ between the two medicines and between providers. The price difference between Mounjaro and Wegovy varies by dose and has shifted since Eli Lilly revised UK list prices in September 2025, worth checking before you commit to either. Our clinical team profile at our prescribers page gives a sense of who reviews these decisions at nume.
Which medicine and which dose suits you is a clinical decision our prescribers make with you, not something a comparison table can settle on its own. Speak to our prescribers by starting a free consultation today.
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