Is Mounjaro Licensed for Weight Loss in the UK? (October 2026)

01 · The short answer

Is Mounjaro licensed for weight loss in the UK?

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

You may see the phrase 'weight loss' used loosely online. The licensed wording is 'weight management'. In practice that means the medicine is approved to help adults reduce body weight and then maintain it, as part of a wider plan that includes diet and activity.

So when someone asks whether Mounjaro is registered, approved or licensed for weight loss, the honest answer is the same in each case. It is a fully licensed UK medicine for this purpose, and it is supplied only on prescription.

02 · Licensed, but for whom

What being licensed does and does not tell you

A licence tells you a regulator has reviewed the evidence on quality, safety and effectiveness for a defined use. It does not tell you that every adult who wants to lose weight should take the medicine. Suitability is decided person by person.

• Licensed use: Mounjaro for weight management in adults, used alongside a reduced-calorie diet and increased physical activity.
• Prescription needed: Mounjaro (tirzepatide) is a prescription-only medicine, supplied only after a consultation reviewed by a GPhC-registered prescriber.
• Product information governs the rest: doses, warnings, interactions and side effects are set out in the product information, which your prescriber applies to your health history.¹¹³

If you are weighing it up, our weight loss clinic page explains the options we offer, and the Mounjaro pen page shows live prices and the consultation.

03 · What to do next

Is this relevant to me, and what should I do next?

It is relevant if you are an adult looking at medically supported weight management and want a treatment that is licensed for it. The sensible next step is a prescriber conversation, not a purchase on impulse. That can be your GP, an NHS service or a regulated online pharmacy.

Check three things before going further. First, that the supplier is on the GPhC register. Ours is GPhC 9012878. Second, that a prescriber reviews your health history. Third, that the medicine is supplied as genuine, packaged product. If you are comparing routes, our guide to a UK registered pharmacy for Mounjaro shows what to look for.

04 · What Mounjaro is

What Mounjaro 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-1.¹ 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

That dual action is what distinguishes Mounjaro from single-action medicines such as semaglutide, sold as Wegovy for weight management and Ozempic for diabetes. If you are unsure how the brands relate, see our explainer on whether Mounjaro is Ozempic.

05 · Licensed use and diet

Licensed alongside diet and activity

The licence is not for the injection alone. Mounjaro is used alongside a reduced-calorie diet and increased physical activity, and individual results vary.¹

Food and movement are therefore part of the prescription, not an optional extra. No food is banned on Mounjaro, including bananas, but some choices make treatment easier and more effective. Prioritise protein at each meal, vegetables and fibre, and regular fluids. Many people feel worse after very fatty, fried or very sugary food, and large portions sit heavily because the stomach empties more slowly, so smaller, slower meals work better. Treatment is licensed alongside a reduced-calorie diet, so the aim is a sustainable deficit, not a perfect food list.

Increased physical activity is part of the licence, not an optional extra. Nothing special is required: the evidence-backed pattern is regular moderate activity (such as brisk walking) plus resistance work for muscle. Start where you are and build; on injection days with early side effects, lighter movement still counts. Exercise also protects against regain if you later stop treatment.

06 · NHS and private access

NHS access versus private prescribing

Being licensed is separate from being available on the NHS. 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).⁴⁶ Full rollout is expected to take years, which is why many people who meet the licensed criteria choose regulated private treatment rather than waiting.

Your GP is the right first conversation if you think you might qualify on the NHS. Some GPs may refer you to a specialist weight-management service. Others will explain where your area is in the rollout. If you decide to go privately, a regulated online pharmacy should run a consultation that is reviewed by a GPhC-registered prescriber, who can decide whether treatment is appropriate for you.

Whichever route you take, the medicine is the same licensed tirzepatide, and the licence conditions apply equally.

07 · Who should be cautious

Who should not take Mounjaro for weight loss?

Mounjaro is not suitable for everyone, and that is why it is prescription-only. You should not take it if you are allergic to tirzepatide or any of its ingredients, and it should not be used during pregnancy or while trying to conceive. Your prescriber will take extra care, or may recommend against treatment, if you have a history of pancreatitis, severe gut or digestive disease, diabetic retinopathy, or gallbladder problems.¹¹³ Always share your full medical history and medicine list during your consultation. Mounjaro must not be used during pregnancy, and it should be stopped at least one month before trying to conceive. If you become pregnant during treatment, stop the medicine and tell your prescriber promptly.

What a consultation should cover includes your medical history, your current medicines and whether you have any condition that affects suitability. Tell your prescriber about everything you take, including insulin or sulfonylureas, where doses may need adjusting because of the risk of low blood sugar.

Contraception deserves a specific mention. Mounjaro slows stomach emptying, which can reduce how well oral contraceptive pills are absorbed. The SmPC advises switching to a non-oral method, or adding a barrier method (such as condoms), for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase.¹

If your answers show Mounjaro is not right for you, a prescriber will say so. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full.

08 · Dosing within the licence

What licensed dosing looks like

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.¹ 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.

Mounjaro is injected under the skin once a week, on the same day each week, at any time of day, with or without food. Each KwikPen contains four weekly doses. Pens are stored in a fridge at 2–8°C and never frozen. 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

Follow the pen's instructions and your prescriber's guidance.

09 · Outside the licence

What is not licensed: microdosing and unregulated supply

Some online advice drifts outside the licence, and it is worth knowing where the line sits. Altering doses outside the licence means unknown dosing accuracy and no safety data.¹

Supply is the other risk. A licensed medicine is only as safe as the route it reaches you by. Be wary of any seller offering to supply without a consultation or prescription, or promising specific results. The MHRA publishes counterfeit medicine alerts and runs the Yellow Card scheme, where you can report suspected fake products and side effects.⁷¹⁹

You can check any UK pharmacy on the GPhC public register.¹² We supply genuine KwikPens through official LillyDirect supply, direct from Eli Lilly's UK distribution.

10 · Realistic results

How much weight can you lose, and how fast?

Weight loss on Mounjaro is gradual by design. 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, so think in months, not days, and judge progress by trend, not individual weigh-ins.¹

For what the evidence shows, see our pages on expected weight loss, predicted weight loss and the biggest weight loss reported.

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.

Early on, 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, and both are normal. Early loss includes water weight, so the trend over weeks matters more than any single weigh-in.

11 · Side effects and safety

Side effects and what to avoid

Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle. Read the patient information leaflet before starting.¹³

Hydration is the practical point. Drinking enough matters more on Mounjaro than usual: reduced appetite means less fluid from food, and vomiting or diarrhoea can dehydrate you quickly, which is the main route to the rare kidney problems reported with this class. Keep water within reach through the day, and treat inability to keep fluids down as a contact-your-clinical-team issue, not something to push through.

On alcohol, there is no direct interaction between Mounjaro and alcohol, but drinking on a reduced appetite and emptier stomach can hit harder than usual, and alcohol adds calories that work against your goals. If you also take insulin or a sulfonylurea, alcohol increases the risk of low blood sugar. Moderation is the sensible rule.

Coffee and tea are fine, as there is no interaction with caffeine. Strong coffee on an empty stomach can aggravate nausea or reflux for some people. 'Coffee rules' on social media have no clinical basis.

Report any suspected side effect through the MHRA Yellow Card scheme.¹⁹

12 · Other licensed options

Other licensed weight-loss medicines in the UK

Mounjaro is not the only licensed route. Liraglutide, sold as Saxenda, is a daily injection supplied at 6mg per millilitre, unlike once-weekly Mounjaro and Wegovy. Orlistat is a licensed capsule, and you can read about orlistat from a licensed supplier.

Newer oral options are emerging, and our guide to what Foundayo is licensed for explains one of them.

Be careful with products marketed as 'natural' alternatives to prescription injections. They are low-cost supplements with no clinical oversight. Their dosing is not standardised, and they do not hold a medicine licence for weight management.

Misspellings and look-alike names also circulate online. If you have seen Majaro or Manjura, these are not different products, so check the brand name carefully.

13 · Telling your GP

Should you tell your GP?

We would encourage you to tell your GP that you are taking Mounjaro. Your GP holds your wider medical record, and keeping them informed helps if you are unwell, start a new medicine or need other treatment.

Medicines can interact, and the product information lists the interactions you need to know about.¹ Insulin and sulfonylureas, for example, may need dose changes, and oral contraceptives may be less well absorbed. If you take the pill, switch to a non-oral method, or add a barrier method (such as condoms), for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase. A clinician who can see everything you take is best placed to spot problems.

Private treatment also includes ongoing monthly reviews, dose-titration and follow-up assessments by our prescribing team, plus side-effect support. Repeat orders re-check suitability, and nothing is shipped automatically.

14 · 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) — stop using Mounjaro and get medical help straight away; pain in the upper right abdomen, fever or yellowing of skin/eyes (possible gallbladder problems) — get medical help straight away; or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing — get medical help straight away. 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