A Plain-English List of Weight Loss Injections Available in the UK

You've heard the names — here's what's actually on the UK list

Picture this: you've been reading about weight loss injections online, seen references to Ozempic, Saxenda, Zepbound and a dozen more, and now you're not sure which of them are real options in the UK. It's a genuinely confusing landscape. So let's sort it out plainly.

The weight loss injections licensed for adults in the UK are Mounjaro and Wegovy. That is the full list for weight management. Saxenda (liraglutide) holds a UK licence for weight management but has largely been superseded in clinical practice by the two newer options. Ozempic contains the same active ingredient as Wegovy (semaglutide) but is licensed for type 2 diabetes, not weight loss, it is not a weight management option through a UK prescriber, and conflating the two causes real confusion for patients. Zepbound is the US brand name for tirzepatide; it does not exist as a UK product and cannot be obtained from any UK pharmacy.

For a broader breakdown of names, brand names and what each medicine contains, our list of all weight loss injections goes through every brand in detail, and if you want a clear overview of which products carry which active ingredients, our weight loss injections names list is a useful companion reference. The NHS medicines page for tirzepatide and the equivalent page for semaglutide give clear, patient-level overviews of what each drug is and how it works, written by NHS clinical editors.

Mounjaro: the dual-action injection on the list

Mounjaro is made by Eli Lilly and delivered via a pre-filled KwikPen containing four weekly doses. Each pen covers one month of treatment. What sets it apart from Wegovy is its mechanism: it activates both the GIP and GLP-1 gut-hormone receptors, slowing gastric emptying and reducing appetite through two pathways simultaneously. It is the only dual-agonist weight management medicine licensed in the UK.

Treatment starts at 2.5 mg. That first dose exists to help your system adjust, not to drive significant weight change. A prescriber increases the dose, typically in four-week steps, through 5, 7.5, 10 and 12.5 mg up to a maximum of 15 mg. In the SURMOUNT-1 trial, published in the New England Journal of Medicine, participants on 15 mg achieved an average body-weight reduction of around 20–21% over 72 weeks. The SURMOUNT-5 trial, also published in NEJM in 2025, compared tirzepatide head-to-head with semaglutide 2.4 mg and found greater average weight loss with tirzepatide.

NICE recommended tirzepatide for NHS use in December 2024 (technology appraisal TA1026), though NHS access is being introduced in phased cohorts with strict eligibility criteria. Private treatment through a regulated pharmacy is currently the most accessible route for most adults who qualify clinically.

Wegovy: the GLP-1 injection and its newer higher dose

Wegovy, made by Novo Nordisk, is a GLP-1 receptor agonist. It works along a single hormonal pathway, reducing appetite and slowing digestion. The standard titration runs from 0.25 mg up to a maintenance dose of 2.4 mg, stepped up roughly every four weeks. In the STEP 1 trial, participants on 2.4 mg lost around 15% of their body weight on average over 68 weeks.

In January 2026 the MHRA approved a higher 7.2 mg dose, and in April 2026 a dedicated single-dose 7.2 mg pen was approved specifically for adults with a BMI of 30 or above. Early trial data at that dose reported average weight loss of around 20.7% over 72 weeks, narrowing the gap with tirzepatide's highest-dose results. Dose availability at any given time is confirmed during a clinical consultation, not assumed in advance.

If cost is part of your thinking, the how much are weight loss injections page covers UK private pricing in honest detail, including what happened to list prices in late 2025. For a side-by-side look at three commonly compared options, the three weight loss injections page is a useful next step.

Practical things to know before starting either injection

Both Mounjaro and Wegovy are subcutaneous injections, meaning you inject into the fatty tissue just beneath the skin, typically at the abdomen, thigh or upper arm, rotating sites each week. The process is straightforward once shown, and most people find it far less daunting than they expected.

Side effects follow a broadly similar pattern for both: nausea, constipation, diarrhoea, indigestion and fatigue are the most commonly reported, usually most noticeable after a new dose and settling within a week or two for most people. The MHRA issued specific guidance in January 2026 noting acute pancreatitis as a known but uncommon side effect requiring urgent attention if you develop severe, persistent stomach pain that radiates to the back. Anyone on either medicine should know that symptom and act on it promptly. Reporting side effects, or flagging a suspect seller, can be done through the MHRA Yellow Card scheme.

Neither medicine is suitable during pregnancy, while breastfeeding, or if you are trying to conceive. Under-18s are not a licensed population for either. Women using oral contraceptives starting Mounjaro need to add a non-oral method for the first four weeks of treatment and after each dose increase, because tirzepatide's effect on gastric emptying can reduce pill absorption.

When a prescription is issued through a regulated UK pharmacy like our service, dispensing follows a same-day clinical review process. The medicine arrives via DPD the next working day, tracked to your door, in plain packaging with nothing on the outside to identify its contents. That matters to a lot of people. If you want to understand the full clinical process before committing to anything, our FAQs page covers the most common questions our prescribers hear.

Ready to find out whether a weight loss injection could be right for you? Check your eligibility with a free consultation and a GPhC-registered prescriber will review your answers the same day.