Drugs Similar to Mounjaro and How They Compare

What the head-to-head trial actually found

For years, comparisons between tirzepatide and semaglutide rested on indirect analysis, looking across separate trials rather than putting both medicines in the same study at the same time. That changed with SURMOUNT-5, published in the New England Journal of Medicine in 2025. The trial enrolled 751 adults living with obesity who did not have type 2 diabetes and ran for 72 weeks. Participants taking tirzepatide lost more body weight on average than those taking semaglutide 2.4 mg, and NICE's appraisal committee noted the indirect comparisons also favour tirzepatide at the highest doses.

It is worth being precise about what that means in practice. Both medicines produced meaningful weight reduction; the question was one of degree, not of whether they work. SURMOUNT-5 found the gap was real and statistically significant, but individual responses vary, the average does not predict what happens to any one person.

NICE incorporated this evidence when it recommended tirzepatide for NHS use in December 2024 (Technology Appraisal TA1026). It is the most recent NICE recommendation in this class, and its eligibility criteria reflect the strength of that trial evidence.

How semaglutide (the closest similar drug) differs mechanically

If you are researching tirzepatide similar products, semaglutide is the medicine you will encounter most often. Sold as Wegovy for weight management, it works by mimicking GLP-1, a gut hormone released after eating. GLP-1 slows gastric emptying, signals fullness to the brain, and influences insulin release. Tirzepatide does all of that, but it also activates GIP receptors, a second gut-hormone pathway that appears to amplify the appetite-suppression and metabolic effects.

The practical upshot is that Wegovy is an effective, well-studied medicine with its own robust trial programme (STEP 1 showed roughly 15% average weight loss over 68 weeks at the 2.4 mg dose). Tirzepatide's dual action appears to add a further layer. Think of it less as one medicine being 'better' and more as two related but distinct mechanisms. The NHS medicines page for tirzepatide covers how the drug works and its side-effect profile in clear, patient-facing language.

Wegovy itself also now exists in a higher 7.2 mg dose, approved by the MHRA in early 2026, with trial data suggesting around 20.7% average weight loss, closing some of the gap with tirzepatide's highest dose. More on that is available through our overview of GLP-1 drugs and how Mounjaro fits in.

Drugs often confused with Mounjaro alternatives

Ozempic appears constantly in conversations about similar drugs, and the confusion is understandable, it contains semaglutide, exactly the same active ingredient as Wegovy. The difference is the licence. Ozempic is authorised in the UK for type 2 diabetes management, not for weight loss. That distinction matters both legally and clinically: the doses differ, the monitoring context differs, and prescribing it outside its licensed indication for weight management is not straightforward.

Rybelsus is oral semaglutide at 3, 7 or 14 mg, again, licensed only for type 2 diabetes. If you have seen mention of an oral semaglutide weight-loss tablet, that is Wegovy tablets, approved by the MHRA in June 2026 at a separate dosing schedule (1.5 mg up to 25 mg). The two products share an active ingredient but carry entirely different licences and are not interchangeable.

Saxenda (liraglutide) is a GLP-1 medicine licensed for weight management in the UK, though it is an earlier-generation option that requires daily rather than weekly injection and generally produces more modest results than either semaglutide or tirzepatide. We cover the distinctions in more detail on our guide to Mounjaro and its drug class. If you are wondering about biosimilar versions of tirzepatide, our Mounjaro biosimilar page explains where things stand with UK licensing on that front.

Choosing between them is a clinical conversation, not a ranking exercise

If you have been searching for drugs similar to Mounjaro because you want to understand your options, that is a sensible place to start. Many people feel a bit overwhelmed by the number of brand names, mechanisms and trial statistics, and it can be hard to know which information applies to the UK specifically. The honest answer is that no comparison table replaces a conversation with a prescriber who can look at your health history.

Eligibility for tirzepatide under its UK licence is BMI 30 or above (or 27 or above with a weight-related condition such as high blood pressure, high cholesterol, type 2 diabetes or obstructive sleep apnoea). Wegovy carries broadly similar criteria. Lower BMI thresholds apply for some ethnic backgrounds under UK guidance. Neither medicine is suitable during pregnancy, while breastfeeding, or for anyone under 18, and there are specific conditions (including personal or family history of medullary thyroid carcinoma) that require careful prescriber review before either drug is appropriate.

For a fuller look at medicines similar to Mounjaro and how they are placed within the UK treatment landscape, that page goes into further depth. Practical information on treatment costs is covered on our Mounjaro cost guide, which explains what a legitimate private prescription actually includes. Our prescribers can walk through which option, if any, makes clinical sense for you, start with a free consultation and a named, GPhC-registered Independent Prescriber will review your answers the same day.