Evaluating the Company Behind Mounjaro for Weight Loss (October 2026)

01 · The verdict

Is Mounjaro a sound choice, and who makes it?

Mounjaro is a licensed UK medicine made by Eli Lilly, with published trial results behind it and a clear prescribing pathway. It suits adults who meet the licensed criteria and want a once-weekly injection alongside diet and activity changes. It does not suit anyone looking for a quick fix or a product that works without lifestyle changes.

Eli Lilly manufactures it, it carries UK licences for weight management and type 2 diabetes, and the main weight-loss trial is published in a peer-reviewed journal.¹²

Supply matters as much as the manufacturer. We are a GPhC-registered pharmacy (registration 9012878) and our Mounjaro comes through official LillyDirect supply, direct from Eli Lilly's UK distribution. These are genuine KwikPens, and all six doses are in stock. Every prescription is reviewed by a GPhC-registered prescriber, not a scoring script.

02 · What it costs

What Mounjaro costs and how to plan a year

Your first 2.5mg pen costs £129.99 with code FIRST40. Switching to us at a higher dose? Your first order at 15mg is £289.99. Every later order is £25 off the standard price, automatically (code DOSE25).

Across the UK pharmacies we track, Mounjaro pens ranged from £143.96 to £339.00 per month at the index check on 11 October 2026. Starting pens ranged from £143.96 to £179.99. The gap between providers for the same dose ran from £27 to £41. See how Mounjaro prices compare between providers, or go straight to the Mounjaro pen prices and consultation.

03 · How to order

How ordering works

Ordering takes three steps, and the consultation is free with no obligation. Our Buy Mounjaro page has the full detail.

• Free online consultation. A short health questionnaire, at no charge. Start your free consultation.
• Prescriber review. A GPhC-registered prescriber reviews your answers. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full.
• Dispatch and delivery. Our registered pharmacy dispenses and ships the same day when you order by 3pm. Delivery is free, next-day, tracked and temperature-controlled. Saturday delivery is £14.99.

Ongoing monthly reviews are included, and repeat orders re-check suitability. Nothing ships automatically. Klarna and pay-monthly options are available, with no subscription lock-in. Mounjaro is a prescription-only medicine, supplied only after a consultation reviewed by a GPhC-registered prescriber.

Counterfeit pens are a real risk when buying outside regulated channels. Be wary of anyone offering to supply Mounjaro without a consultation or prescription. You can check any UK pharmacy on the GPhC register. Report suspected counterfeits or side effects through the MHRA Yellow Card scheme.⁷¹⁹

04 · Who makes Mounjaro

Who makes Mounjaro, and what is it?

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. It comes as a pre-filled multi-dose pen, called a KwikPen, in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg.¹

The manufacturer is the first thing to check when you evaluate any prescription drug company. A recognisable maker is not proof that a medicine suits you, but it tells you where the product comes from, who holds the licence and who publishes the trial data. For Mounjaro, the Summary of Product Characteristics and the Patient Information Leaflet are both public on the electronic medicines compendium, and you can read them before you decide.¹¹³

It helps to keep them apart. Eli Lilly makes the medicine. A pharmacy such as ours dispenses it to you after a prescriber has reviewed your consultation. The two roles are different, and a seller's registration matters as much as the manufacturer's name. We are registered with the General Pharmaceutical Council under number 9012878, and our Mounjaro comes through official LillyDirect supply, direct from Eli Lilly's UK distribution.

Some pages on the web describe Mounjaro as approved only for diabetes and say that using it for weight loss is off-label. That is not the position in the UK, where the product is licensed for weight management in adults as well as for type 2 diabetes. The weight-management licence comes with conditions: a qualifying BMI and use alongside a reduced-calorie diet and increased physical activity.

If you want to see how Eli Lilly sits alongside other makers of weight-loss injections, our overview of the weight loss injections company landscape sets the products side by side. If you are specifically comparing with the Danish maker of a rival injection, read our guide to the Danish company weight loss drug question.

Finally, check the pen. Genuine Mounjaro arrives in a KwikPen with the patient information leaflet. Needles, a sharps bin and injection guidance come with every order from us. If anything looks wrong on delivery, contact our support team (Monday to Friday, 9am to 5pm) and do not use the pen.

05 · How tirzepatide works

How tirzepatide works

Tirzepatide activates 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.¹¹¹

That dual action is what distinguishes Mounjaro from single-action GLP-1 medicines such as semaglutide, sold as Wegovy and Ozempic. It is a statement about mechanism, not a promise about any one person's result. Whether the two-receptor design translates into a better outcome for you is something only a prescriber can discuss with you, using your history.

Because the stomach empties more slowly, portions that once felt normal can feel heavy. This is also the reason behind many of the common digestive side effects, and the reason smaller, slower meals tend to work better. Mounjaro slows stomach emptying, which can reduce how well oral contraceptive pills are absorbed, so 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

Tirzepatide has a half-life of about five days. After a final dose it takes roughly 4 to 5 weeks to clear the system. There is no way to speed this up, and nothing needs doing while it clears. That matters if you are planning around surgery, pregnancy or a change of treatment, because the medicine does not leave your body the day you stop injecting. 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. Raise any such plans with your prescriber early.

The weekly schedule is part of the design. You inject once a week, on the same day where possible, using a pre-filled pen. Follow the pen's instructions for the injection itself. Doses are stepped up gradually, starting at 2.5mg, and each strength is a separate pen.

Your prescriber decides when to move up a strength, and many people stay on a lower dose if it works for them and they tolerate it well. Our team handles dose titration and follow-up assessments as part of the ongoing monthly reviews. If you want to see how this fits into a wider programme, read our guide to Mounjaro weight loss treatment in the UK.

One more distinction is worth making. Liraglutide, sold as Saxenda and in products such as Erly, is supplied at 6mg per millilitre and is a daily injection, unlike once-weekly Mounjaro and Wegovy. Frequency of injection is a practical difference that some people weigh heavily.

06 · What the trials show

What the SURMOUNT-1 trial shows

In SURMOUNT-1, a 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.² These are trial averages. Individual results vary, and treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.

The same trial reports how many people reached particular thresholds. At 72 weeks, 85% of participants on 5mg, 89% on 10mg and 91% on 15mg had lost at least 5% of their body weight. Half of participants on 10mg and 57% on 15mg lost at least 20% of their body weight.²

Percentages are easier to judge with a worked example. For someone starting at 100 kg, 15% is about 15 kg, 19.5% is about 19.5 kg and 20.9% is about 21 kg. That is straight arithmetic on the trial averages and not a forecast for you, because trial averages do not predict your own result. Starting weight, dose reached, how long you stay on treatment, diet and activity all matter.

When you evaluate any drug company's claims, look for three things: a named trial, a stated duration and a comparison group. SURMOUNT-1 gives all three. Be cautious about marketing that quotes dramatic weight-loss claims without naming a trial, or that mixes numbers from different studies as if they were a head-to-head contest. Different trials enrol different people over different periods, so their headline figures should not be set side by side.

Where a direct comparison exists, it is clearer. SURMOUNT-5, the first large head-to-head trial, compared tirzepatide with semaglutide directly in people with obesity.¹⁵ For maintenance, SURMOUNT-4 looked at continued tirzepatide treatment for keeping weight off.¹⁴

It is also worth being clear about what the trial population did. Participants combined the medicine with a reduced-calorie diet and increased physical activity. The licence mirrors that approach, which is why our prescribers will talk with you about food, protein, movement and fluids at your reviews and not only about the dose.

Finally, a note on expectations. Some people lose weight more slowly than the averages suggest and some more quickly. A pen is not a verdict on your effort. If progress stalls, your prescriber can review your dose, your side effects and your routine with you.

07 · Eligibility and prescribing

Who can be prescribed Mounjaro

Mounjaro is licensed for weight management in adults with a BMI of 30 or above, or a BMI between 27 and 30 with at least one weight-related condition. Examples are high blood pressure, high cholesterol, obstructive sleep apnoea, cardiovascular disease, prediabetes or type 2 diabetes. It must be used alongside a reduced-calorie diet and increased physical activity.¹

Meeting the BMI line does not mean you will automatically be prescribed it. A prescriber assesses your BMI, medical history and current medicines before deciding whether it is suitable for you. That assessment is the reason the consultation exists, and it is why we describe the review as a clinical decision by a GPhC-registered prescriber, not a form that scores you.

Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full. That is a useful test of any online provider: does it have a real route for saying no? Ours does.

You will be asked about conditions and medicines. Be complete. Some combinations need care. For example, if you take insulin or a sulfonylurea, doses may need adjusting because of the risk of low blood sugar. 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. Tell the prescriber about everything you take, including supplements.

Eligibility is also ongoing. Repeat orders re-check suitability and there is no auto-shipping. At your monthly reviews the team looks at side effects, dose and progress, and decides with you whether to continue, hold or step up.

If you want a plain-English answer to whether the medicine needs a prescription at all, read our guide on whether Mounjaro is a prescription drug. For the wider class, see whether GLP-1 medicines are prescription drugs.

People often ask how to get approved for weight-loss drugs in general. In practice, the route is the same whichever setting you use: an assessment of your BMI, your health conditions and your medicines, followed by a prescriber's decision. NICE sets the criteria for NHS use, and the licence sets the criteria for private prescribing.⁴

08 · NHS and private access

NHS versus private Mounjaro

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. 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.

That is the honest picture. If you sit in an early NHS group, ask your GP practice about the pathway, and read the NHS's own information on the medicine.⁵ You will pay only the NHS prescription charge, which is £9.90 in England, where a charge applies.

If you do not yet fall into an early group, you have two broad choices: wait for the rollout to reach you, or choose regulated private treatment. The private licence is wider. A BMI of 30 or above, or 27 to 30 with a weight-related condition, can qualify, though a prescriber still has to agree that the medicine is suitable.¹

Your GP or local NHS service can confirm where you currently stand.

Private treatment is not a shortcut around clinical standards. Your consultation is reviewed by a GPhC-registered prescriber, treatment is licensed alongside diet and activity, and ongoing monthly reviews are included. The difference is access and timing, plus the cost, which you carry yourself.

Some people prefer to stay inside the NHS, with its local support services. Others want to start sooner and accept the cost. If you choose private care, choose a registered pharmacy, check the GPhC register, and never buy from anyone offering to supply without a consultation or prescription. Our full list of weight loss treatments shows what else we offer if Mounjaro is not the right fit.

09 · Living well on treatment

Food, exercise and daily habits on treatment

Treatment works best alongside a reduced-calorie diet and increased physical activity, and that is part of the licence, not advice added for effect.¹ A drug company's trial result only carries over to you if you do what the trial participants did.

Food. No food is banned on Mounjaro, including bananas. 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. Smaller, slower meals work better. The aim is a sustainable calorie deficit, not a perfect food list.

Protein and muscle. Some of any rapid weight loss comes from lean tissue, and protecting muscle protects your metabolism, strength and appearance. The two levers are adequate protein, with a protein source at every meal (harder when appetite is low), and resistance exercise two or more times a week. This matters more, not less, as the dose rises and appetite falls.

Exercise. 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.

Hydration. Drinking enough matters more 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, and treat inability to keep fluids down as a reason to contact your clinical team, not something to push through.

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

Coffee. There is no interaction between Mounjaro and caffeine, so coffee and tea are fine. Strong coffee on an empty stomach can aggravate nausea or reflux for some people, and high-calorie coffee drinks are an easy place for the deficit to leak. "Coffee rules" circulating on social media have no clinical basis.

Vitamins. No supplement is required, but eating much less can leave gaps, so a standard daily multivitamin is a reasonable safety net. Discuss anything beyond that with a pharmacist. Our free GLPTrackr companion app (iOS and Android) can help you keep track of doses, meals and progress.

10 · Other options compared

Other weight-loss options, Qsymia and Medtronic

Qsymia and Medtronic are sometimes mentioned alongside weight-loss treatment. If a prescriber has suggested a different product, ask them for current figures and how it fits your health history.

Wegovy (semaglutide) is a once-weekly injection whose pens are 0.25mg, 0.5mg, 1mg, 1.7mg and 2.4mg. Titration steps up after at least 4 weeks and reaches the 2.4mg maintenance dose from week 17, which is the licensed maintenance dose for weight management.¹⁸ Liraglutide, sold as Saxenda and in products such as Erly, is a daily injection supplied at 6mg per millilitre. Mounjaro and Wegovy are both once weekly. Wegovy tablets and Foundayo tablets also exist; see current information on our product pages.

For a direct tirzepatide-versus-semaglutide comparison, SURMOUNT-5 is the first large head-to-head trial.¹⁵ Our weight loss treatments overview lays out the options.

You may also see so-called "poor man's Ozempic" products and supplements marketed as "natural GLP-1 boosters". They are not equivalents and are not substitutes for prescribed treatment. They are low-cost supplements with no clinical oversight, and their dosing is not standardised. Dramatic weight-loss claims attached to them should be treated with scepticism.

A few questions help you evaluate any weight-loss product, whoever makes it. Is it licensed in the UK for your situation? Who reviews your suitability? Is there a named trial behind the numbers? Does the seller appear on a regulator's register? Will there be follow-up if you have side effects?

Stopping is part of the decision too. After a final Mounjaro dose it takes roughly 4 to 5 weeks to clear the system, and nothing needs doing while it clears. Exercise helps protect against regain, so keep up the habits you built. Talk to your prescriber before stopping, and report any suspected side effect through the Yellow Card scheme.¹⁹

Mounjaro (tirzepatide) is a prescription-only medicine, supplied only after an online consultation reviewed by a GPhC-registered prescriber. It is used alongside a reduced-calorie diet and increased physical activity. Individual results vary. This page is information, not a substitute for medical advice.

11 · 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