What are the 3 weight loss injections available in the UK right now?

Step 1, understand what separates the three medicines, because the mechanism matters

Liraglutide (Saxenda) was the first of the three to reach the UK market for weight management. It works by activating GLP-1 receptors, a set of hormone pathways involved in appetite and blood-sugar control. It requires a daily injection, and in clinical trials it produced average weight loss in the region of 5–8% of body weight. That was a meaningful step forward when it launched, but the landscape has shifted considerably since.

Semaglutide (Wegovy) is also a GLP-1 receptor agonist, but a more potent, longer-acting version that needs only a once-weekly injection. In the STEP 1 trial, published in the New England Journal of Medicine, semaglutide 2.4mg produced an average weight reduction of around 15% over 68 weeks. The NHS medicines page for semaglutide covers how it works in plain language.

Tirzepatide (Mounjaro) is the newest of the three and the only one that activates two gut-hormone receptors simultaneously, both GLP-1 and GIP. That dual action appears to produce stronger appetite suppression and greater average weight loss than a single receptor target alone. In the SURMOUNT-1 trial, participants using the highest dose (15mg) lost an average of around 20–21% of body weight over 72 weeks. The NHS medicines page for tirzepatide explains the mechanism clearly.

All three are given by subcutaneous injection. Saxenda is daily; Wegovy and Mounjaro are once weekly. If you're still getting to grips with the broader landscape, our page on what the new injections for weight loss actually are gives a helpful grounding before you compare the specifics. That weekly rhythm makes a practical difference to most people's experience of treatment.

Step 2, know who qualifies, because eligibility isn't the same for all three

The licensed eligibility criteria for Mounjaro and Wegovy are broadly similar: adults with a BMI of 30 or above, or a BMI of 27 or above alongside at least one weight-related health condition such as type 2 diabetes, high blood pressure, high cholesterol or obstructive sleep apnoea. Lower BMI thresholds can apply for some ethnic backgrounds under UK guidance. Saxenda carries comparable licensing criteria, though it's now rarely the first-choice option in clinical practice.

On the NHS, access is considerably more restricted. NICE's appraisal of tirzepatide (TA1026) limits NHS prescribing to adults with a BMI of 35 or above alongside at least one qualifying comorbidity, accessed through a structured weight management pathway. The phased rollout means most people who are technically eligible will wait. Wegovy on the NHS is similarly constrained, available through specialist services with long waiting lists in most areas. You can read more about what all the current weight loss injections look like in terms of access on our full guide to all the weight loss injection options.

BMI alone is never the whole story. A prescriber considers your full medical history, any contraindications, and your goals before deciding whether treatment is appropriate, and which medicine is the better fit.

Step 3, find out what each one actually costs in context, and what legitimacy looks like

Cost is the thing many people come to this page wanting to understand. Since Eli Lilly raised Mounjaro's UK list price in September 2025, typical private prices have ranged from roughly £149 to £375 per month depending on dose and provider, figures that have been widely reported. Our weight loss injections prices page gives a fuller picture of what drives those numbers.

What a headline price often doesn't tell you is what's included. Consultation fees, prescription charges, delivery and aftercare can all arrive as extras. That's worth factoring in before comparing numbers. It's also worth remembering that these are Prescription-Only Medicines, anyone offering them without a clinical assessment is operating outside UK law. The MHRA has seized around 20 million doses of illegally traded weight-loss medicines worth approximately £45m, including counterfeit pens that in some cases contained insulin. You can read more about what legitimate access looks like and report any suspect sellers via the MHRA's Yellow Card service.

At nume, one transparent price covers the consultation, prescription, treatment, and free next-working-day tracked delivery, no subscription, no hidden charges. A real clinician reviews every consultation the same day it's submitted. If you're weighing up your options, the weight loss treatments overview is a good place to start.

A note on where Saxenda sits in 2025 and beyond

Saxenda remains a licensed option in the UK and some people continue to use it, but it's worth being straightforward: the clinical evidence for both Mounjaro and Wegovy shows considerably greater average weight loss, at comparable or lower injection frequency. Most prescribers working in weight management will discuss the newer options first. If you want a clear explanation of what the weight loss injections are and how they differ from one another, that guide covers the key distinctions in plain terms.

Honestly, it can feel overwhelming trying to compare options when every article uses different names and different numbers. The clearest route through is a conversation with a prescriber who can weigh your history against the evidence. If you're specifically trying to understand what the two main weight loss injections are that dominate private prescribing right now, that page sets out the comparison directly. Our clinical team (including our clinical lead) reviews every case personally, and the consultation is free. If you have questions before starting, the FAQs page covers the things people ask most often.