Mounjaro and Wegovy Difference (October 2026)

01 · The verdict

Which is right for you: Mounjaro or Wegovy?

Neither is the right choice for everyone, because both are effective, licensed treatments and the better fit depends on your health profile, tolerance and prescriber advice.¹⁵ In the first large head-to-head trial, SURMOUNT-5, average weight loss was higher on tirzepatide (Mounjaro) than on semaglutide 2.4mg (Wegovy).¹⁵

Mounjaro may suit adults whose prescriber judges it appropriate for their health profile, and who are comfortable with a six-step dose ladder that goes up to 15mg. Wegovy may suit adults whose prescriber prefers semaglutide, who are already established on it, or who want a ladder with one maintenance dose, 2.4mg.¹⁸

Both need a prescriber to confirm they are suitable for you. If you want a fuller walk-through, our UK Wegovy and Mounjaro guide covers the same ground from a patient's angle.

02 · Side by side

Mounjaro and Wegovy compared in one table

Trial figures are averages and individual results vary. Both treatments work alongside a reduced-calorie diet and more physical activity.

03 · Cost

How much do Mounjaro and Wegovy cost?

Your first Mounjaro 2.5mg pen costs £129.99 with code FIRST40 (standard price £169.99), and the Wegovy first pen is £99.99 as a first-order price. After a first order, every later order is £25 off the standard price (code DOSE25). You can see live doses on the Mounjaro pen page and the Wegovy pen page.

Across the UK pharmacies we track, Mounjaro pens range from £143.96 to £339.00 per month depending on dose and provider (checked 10 October 2026). If you step up after 4 weeks on each dose, your first four pens (2.5mg to 10mg) cost £959.96 at standard prices, before discounts. A first year costs £2,711.88 if you stay on 5mg after your 2.5mg starting pen, up to £3,599.88 if you step up through every dose to 15mg. For a detailed breakdown, see our price comparison of the two injections.

04 · How they work

How Mounjaro and Wegovy work differently

Mounjaro contains tirzepatide, which activates 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

Wegovy contains semaglutide, a single-action GLP-1 medicine.¹ That dual-versus-single action is what separates the two on paper. Mounjaro is the brand name for tirzepatide, so if you are wondering whether the two names mean different things, our page on the tirzepatide and Mounjaro difference explains it.

Tirzepatide has a half-life of about five days, so after a final dose it takes roughly 4–5 weeks to clear the system. There is no way to speed this up, and nothing needs doing while it clears.¹

05 · Trial evidence

What the trials show about weight loss

In SURMOUNT-5, the first large head-to-head trial, 751 adults took tirzepatide or semaglutide 2.4mg for 72 weeks. Average loss was 20.2% of body weight on tirzepatide against 13.7% on Wegovy, or 22.8 kg against 15.0 kg.¹⁵

The proportions reaching each threshold in SURMOUNT-5 were:

• At least 10% of body weight: 81.6% on tirzepatide vs 60.5% on semaglutide
• At least 15%: 64.6% vs 40.1%
• At least 20%: 48.4% vs 27.3%
• At least 25%: 31.6% vs 16.1%¹⁵

Each medicine also has its own pivotal trial, and these should be read separately rather than set side by side. In SURMOUNT-1, 2,539 adults taking tirzepatide lost on average 15% of body weight on 5mg, 19.5% on 10mg and 20.9% on 15mg over 72 weeks, against 3.1% with lifestyle changes alone.² In STEP 1, adults on semaglutide 2.4mg lost on average 14.9% over 68 weeks, compared with 2.4% on placebo.⁹

As a worked example, for someone starting at 100 kg, 20.9% is about 21 kg. That is a trial average, not a forecast: trial averages do not predict your own result, and treatment works alongside a reduced-calorie diet and increased physical activity.

06 · Doses and titration

Are Wegovy and Mounjaro doses different?

Yes, the doses are completely different and not interchangeable. Mounjaro comes in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg.¹ Wegovy pens are 0.25mg, 0.5mg, 1mg, 1.7mg and 2.4mg once weekly, stepping up after at least 4 weeks and reaching the 2.4mg maintenance dose from week 17.¹⁸ The 2.4mg dose is the licensed maintenance dose for weight management.¹⁸

So a 0.5mg Wegovy dose is not the same as a 5mg Mounjaro dose. They are different molecules measured on different scales, and milligrams cannot be compared across them.

Your prescriber decides your Mounjaro dose and when to step up, based on how you respond and tolerate treatment.

07 · Side effects

Side effects: what is the downside of Wegovy and Mounjaro?

The main downside of Wegovy in its pivotal trial was gastrointestinal side effects. In STEP 1, these were reported by 74.2% of people on semaglutide 2.4mg compared with 47.9% on placebo, and 7.0% stopped treatment because of side effects, compared with 3.1% on placebo.⁹

That is also the answer to why some people stop Wegovy: for a minority, side effects are the reason. Mounjaro also commonly causes digestive side effects: nausea, diarrhoea, vomiting, constipation and abdominal discomfort affect more than 1 in 10 people. Your prescriber will talk you through what to expect on either medicine.¹

Report any suspected side effect through the Yellow Card scheme.¹⁹ For more, see Wegovy and Mounjaro side effects compared.

08 · Switching

Switching between Wegovy and Mounjaro

There is no licensed direct conversion between semaglutide and tirzepatide, so switching is always done under prescriber supervision. Typically the previous medicine is stopped, a washout interval is observed, and Mounjaro is started at a dose your prescriber judges appropriate. That is often the 2.5mg starting dose, sometimes adjusted based on your history.¹

Never run two GLP-1 medicines together. Mounjaro must not be combined with other GLP-1 medicines, unlicensed research peptides such as retatrutide (which has no UK licence) or compounded copies. These combinations have no safety data and no regulated supply chain, and anything that promises faster results outside a licensed pathway is a warning sign.¹

Some people move from Wegovy to Mounjaro because Wegovy was not tolerated or no longer suited them; the prescriber decides when to switch and which dose to start on.

09 · Ozempic, tablets and NHS

Ozempic, tablets and NHS access

Ozempic is semaglutide licensed for type 2 diabetes, not a UK weight-loss medicine, and prescribing it privately for weight loss is off-label. The licensed weight-management injections are Mounjaro and Wegovy, so "Mounjaro vs Ozempic" for weight loss is really Mounjaro vs Wegovy. See how Mounjaro and Ozempic differ.¹⁸

There is no tablet form of Mounjaro. Two GLP-1 weight-loss tablets are now licensed in the UK: Wegovy tablets (oral semaglutide), approved by the MHRA in June 2026, and Foundayo (orforglipron), approved in August 2026. They are different medicines from Mounjaro, with their own dosing, eligibility checks and trial results, and both are prescription-only. See the full range of weight loss treatments for current tablet prices.²⁰²¹

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 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. NHS access to Wegovy runs through specialist weight-management services; ask your GP.

10 · Getting started

How to get Mounjaro from EverydayMeds

We are a GPhC-registered UK online pharmacy (registration 9012878), and our Mounjaro comes through official LillyDirect supply direct from Eli Lilly, with all six doses in stock. Ordering takes three steps:

• Free online consultation: a short health questionnaire with no charge and no obligation.
• Prescriber review: reviewed by a GPhC-registered prescriber, not a scoring script. 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: same-day dispatch when ordered by 3pm, then free next-day tracked delivery in temperature-controlled packaging.

Ongoing monthly reviews are included, and there are no subscriptions. Start your free consultation and the prescriber will advise which medicine suits you.

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