Tirzepatide and Semaglutide Tablets: Comparing Your Two Main Options

What you are actually deciding between

Tirzepatide (Mounjaro) and semaglutide are related but distinct medicines. Semaglutide activates a single gut-hormone receptor (the GLP-1 receptor) to reduce appetite and slow gastric emptying. Tirzepatide does the same thing, and then goes further by also activating the GIP receptor, making it the only dual-agonist weight-loss medicine licensed in the UK. Whether that second mechanism translates into meaningfully better results for you depends on factors a prescriber weighs up, not a comparison article.

Semaglutide is available for weight management in two forms: the weekly Wegovy injection and, as of 11 June 2026 when the MHRA granted approval, the first oral GLP-1 medicine licensed for weight loss in the UK — the Wegovy tablet. Tirzepatide is currently available as the Mounjaro weekly injection only; there is no licensed tirzepatide tablet in the UK at the time of writing. So in practice, if you are comparing tablets specifically, you are weighing oral semaglutide against an injected tirzepatide regimen, which is a meaningfully different lifestyle consideration as well as a clinical one.

The full breakdown of how these two molecules differ covers the receptor science in more detail if that helps your thinking.

What the evidence actually shows

The most direct head-to-head data comes from the SURMOUNT-5 trial, published in the New England Journal of Medicine in 2025, which ran for 72 weeks in adults with obesity and no diabetes. Tirzepatide produced greater average weight reduction than semaglutide 2.4mg, and NICE's appraisal of tirzepatide (TA1026) notes this finding when discussing indirect comparisons.

For the Wegovy tablet specifically, the OASIS 4 phase-3 trial (307 adults, 64 weeks) reported roughly 13.6% average weight loss versus around 2.4% on placebo. Among participants who stayed fully adherent, that figure reached approximately 17%. The Wegovy injection at the standard 2.4mg maintenance dose produced around 15% average reduction over 68 weeks in the STEP 1 trial, as reported in the New England Journal of Medicine STEP 1 paper. Tirzepatide at 15mg reached around 20–21% in the SURMOUNT-1 trial.

Numbers across trials should be read cautiously, different populations, different follow-up periods, different definitions of adherence. The table below puts the key figures side by side.

One practical check worth doing before any further research: look up the GPhC register at pharmacyregulation.org/registers and confirm any online pharmacy you consider is listed. It takes under a minute and tells you immediately whether you are dealing with a regulated UK pharmacy.

Lifestyle fit: injections versus a daily tablet

The Wegovy tablet's approval matters most to people for whom weekly self-injection is a genuine barrier, needle anxiety, travel frequency, workplace constraints. Room-temperature storage means no reliance on a hotel minibar fridge. The trade-off is a demanding morning routine: the tablet must be taken on an empty stomach with a small amount of plain water, with a minimum 30-minute wait before any food, drink other than water, or other oral medicines. For some people that fits naturally into an early morning; for others it genuinely disrupts an established routine.

Tirzepatide's injection schedule (once weekly, rotating between the abdomen, thigh, or upper arm) is a brief, habitual action for most people within a few weeks. The dual mechanism means that, on current evidence, it tends to produce greater average weight reduction than either form of semaglutide, and our Wegovy v Mounjaro comparison sets out how the two medicines stack up across cost, side effects, and trial results if you want a fuller picture. Whether that gap matters for your situation, and whether injection is a problem or not, is exactly the kind of thing a prescriber discusses with you at consultation. The semaglutide or tirzepatide guide goes deeper into this decision if you want to read further before speaking to anyone.

It is also worth knowing that switching between these medicines (for example, moving to tirzepatide after a period on semaglutide) is something some patients do under clinical guidance, and if you are wondering whether semaglutide and tirzepatide can be taken together, that is a question our prescribers are asked regularly, as is whether it is safe to mix tirzepatide and semaglutide in any form.

Eligibility and what a prescriber considers

Both tirzepatide and Wegovy (injection) are licensed for adults with a BMI of 30 or above, or a BMI of 27 or above alongside at least one weight-related condition such as high blood pressure, raised cholesterol, or obstructive sleep apnoea. The Wegovy tablet carries the same core threshold. Across all three, a prescriber also reviews your medical history, current medicines, and any contraindications before deciding which, if any, is appropriate. BMI alone is not the full story.

NHS access follows different criteria. NICE's appraisal of tirzepatide (TA1026) is being rolled out in phased cohorts; Wegovy on the NHS requires referral to a specialist weight management service under TA875 and waiting lists can be long. The Wegovy tablet has not yet been appraised by NICE, so it is currently available through private prescription only. At nume, the private route means no referral and no waiting list, just a clinical assessment to confirm suitability. For a broader look at weight-loss treatment options available through our pharmacy, the overview page covers all three in context.

Which option suits you is a clinical decision. Our prescribers work through the relevant factors with every patient individually, there is no algorithm involved, and no pressure toward one medicine over another.