What's the Name of the Weight Loss Injection? UK Guide (October 2026)

01 · The short answer

The names of the main weight loss injections in the UK

The three names you will see most often are Mounjaro, Wegovy and Saxenda. Each is a brand name for a different active ingredient, and each is a licensed prescription medicine used alongside a reduced-calorie diet and increased physical activity.

Semaglutide is also sold as Ozempic, which is licensed for type 2 diabetes only and is not a UK weight-loss medicine. That is why you sometimes hear 'Ozempic' used as a catch-all, although Wegovy is the brand licensed for weight management.

02 · Your decision

Which name is relevant to you?

The right name depends on your health, your goals and what you tolerate, so the choice is a prescriber's, not a search engine's.

Mounjaro is the medicine we supply. It is the brand name for tirzepatide, a once-weekly injectable prescription medicine made by Eli Lilly. In the UK it is licensed for weight management in adults and for type 2 diabetes. It comes as a pre-filled multi-dose pen (KwikPen) in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg.¹

Your first 2.5mg pen costs £129.99 with code FIRST40 (standard price £169.99), and every later order is £25 off the standard price. Wegovy's first pen starts at £99.99 as a first-order price.

03 · Next step

What to do next

If a once-weekly injection sounds right, the next step is a free online consultation, reviewed by a GPhC-registered prescriber. You can start from our weight loss clinic or go straight to the Mounjaro product page for doses and current availability; all six doses are in stock. If you are unsure which injection to ask for, the prescriber can talk through the options with you.

04 · Mounjaro explained

Mounjaro (tirzepatide): what it is and how it works

Mounjaro is the brand name for tirzepatide, a once-weekly injectable prescription medicine made by Eli Lilly. In the UK it is licensed for weight management in adults and for type 2 diabetes.¹

Tirzepatide is the first treatment of its kind to activate two natural gut-hormone receptors at once: GIP and GLP-1. Together these help regulate appetite, slow how quickly the stomach empties, and improve the way the body responds to insulin. In practice, most people feel fuller sooner and less hungry between meals, which supports a reduced-calorie diet.¹

This dual action is what distinguishes Mounjaro from single-action medicines such as semaglutide (Wegovy/Ozempic).

In the SURMOUNT-1 trial of 2,539 adults, people taking tirzepatide alongside diet and exercise lost on average 15% of their body weight on 5mg, 19.5% on 10mg and 20.9% on 15mg over 72 weeks, compared with 3.1% with lifestyle changes alone. These are trial averages — individual results vary, and treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.²

05 · Wegovy and Ozempic

Wegovy (semaglutide) and the Ozempic confusion

Wegovy is the brand name for semaglutide when it is used for weight management, and it is a once-weekly injection. Its pens come as 0.25mg, 0.5mg, 1mg, 1.7mg and 2.4mg, and the dose steps up after at least four weeks, reaching the 2.4mg maintenance dose from week 17. The 2.4mg dose is the licensed maintenance dose for weight management.¹⁸

Ozempic contains the same active ingredient but carries a different brand name and a different licence. When people say 'the Ozempic jab', they often mean a semaglutide injection in general. For weight management specifically, the name to look for is Wegovy.

If you are weighing the two, ask your prescriber which fits your health history and how you tolerate side effects.

06 · Saxenda and liraglutide

Saxenda and other liraglutide products

Saxenda is the brand name for liraglutide, and it is a daily injection, unlike once-weekly Mounjaro and Wegovy. Liraglutide is supplied at a concentration of 6mg per millilitre, and other products, such as Erly, contain the same ingredient.

The daily routine is the practical difference most readers notice. A medicine you inject every day asks more of your memory, your supplies and your travel planning than a weekly pen. Your prescriber can advise on what to expect with liraglutide.

If you have seen an unfamiliar brand name and wonder whether it is liraglutide, check the active ingredient on the packaging and ask a pharmacist. Our page on the Erly liraglutide injection covers one such product in more detail.

07 · Names that mislead

Other names you may come across

Some products described as weight loss injections are not weight loss medicines at all. A brand name is not evidence that something is licensed for weight management, so it is worth checking each one.

Some are real medicines used for entirely different conditions. Our pages on the Zoladex injection, the Enbrel injection and the epinephrine injection explain why a medicine for another purpose is not a weight loss treatment. Others are marketing labels or unfamiliar names; see our notes on the Majorna injection and the 'retro' weight loss injection.

Three habits protect you. Check that the active ingredient is one of those in the table. Be suspicious of anyone offering to supply without a consultation or prescription. And report any suspected counterfeit or side effect through the MHRA Yellow Card scheme.⁷

Cheap supplements sold as natural alternatives are a different category again. They are available cheaply without assessment, have no clinical oversight and are not comparable with the licensed injections.

08 · Starting and dosing

How Mounjaro dosing works once you have the name

Everyone starts Mounjaro on 2.5mg once a week. This starting dose is about letting your body adjust, not about weight loss itself. After at least 4 weeks the dose increases to 5mg, and can then step up by 2.5mg at a minimum of 4-week intervals (7.5mg, 10mg, 12.5mg) up to a maximum of 15mg weekly, depending on how you respond and tolerate it. Many people settle at a maintenance dose of 5mg, 10mg or 15mg — higher is not automatically better, and your prescriber will guide the right pace.¹

Mounjaro is injected under the skin (subcutaneously) once a week, on the same day each week, at any time of day, with or without food. Each KwikPen contains four weekly doses.¹³ Needles, a sharps bin and injection guidance come with every order.

Keep Mounjaro pens in a fridge at 2–8°C and never freeze them. Once in use, a pen can be kept out of the fridge not above 30°C for up to 30 days, after which it should be discarded.¹

A new customer's first order is £40 less, and every later order is £25 less.

09 · Pace of results

How quickly do weight loss injections work?

Weight loss on Mounjaro is gradual by design, so think in months rather than days. The first weeks on 2.5mg are an adjustment phase and losses are usually modest; most measurable progress builds from 5mg onward, month by month. Trials measured results at 72 weeks, and judging progress by trend matters more than any individual weigh-in.¹

The 2.5mg starting weeks are about adjustment, and experiences differ widely: some people notice appetite change and early loss in week one, others feel little until a higher dose — both are normal. Early loss includes water weight, so the trend over weeks matters more than any single weigh-in.¹

Treatment response is reviewed by your prescriber: if you have lost less than 5% of your starting weight after 6 months on the highest dose you can tolerate, your prescriber will discuss whether continuing or stopping is right for you.¹

That review is built into our ongoing monthly clinical reviews, alongside dose-titration and side-effect support from the prescribing team.

10 · Serious side effects

Serious side effects: when to get help straight away

Serious side effects are uncommon but need urgent attention. Seek immediate medical help for: severe, persistent stomach pain that may spread to your back, with or without vomiting (possible pancreatitis); pain in the upper right abdomen, fever or yellowing of skin/eyes (possible gallbladder problems); or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing. If you take insulin or a sulfonylurea alongside Mounjaro, watch for low blood sugar (shakiness, sweating, confusion) — your prescriber may need to adjust those medicines.¹

11 · NHS and private access

Getting a weight loss injection: NHS and private routes

Mounjaro is available on the NHS, but access is being phased in over several years. NICE recommends it for adults with a BMI of at least 35 plus at least one weight-related condition, and the NHS primary-care rollout began in June 2025 with the highest-need groups first (initially BMI 40+ with four or more qualifying conditions).⁴ Full rollout is expected to take years, which is why many people who meet the licensed criteria choose regulated private treatment rather than waiting. NHS access to Wegovy runs through specialist weight-management services; ask your GP.

Privately, the route is simple. First comes a free online consultation, a short health questionnaire with no charge and no obligation. Second, your order is reviewed by a GPhC-registered prescriber; payment is taken when you place the order, and if the prescriber decides the treatment is not suitable, the order is refunded automatically in full. Third, our registered pharmacy dispenses and dispatches, with same-day dispatch when ordered by 3pm, and free next-day tracked delivery in discreet, temperature-controlled packaging. Our guide to buying weight loss injections in the UK covers the process step by step.

We are a GPhC-registered pharmacy (registration 9012878), and our Mounjaro comes from official LillyDirect supply, meaning genuine KwikPens direct from Eli Lilly's UK distribution.