Which Has Better Results: Ozempic or Mounjaro? (October 2026)

01 · The verdict

Which has better results, Ozempic or Mounjaro?

On average, Mounjaro has delivered greater weight loss than semaglutide in the first large head-to-head trial. In SURMOUNT-5, adults on tirzepatide lost on average 20.2% of body weight over 72 weeks, versus 13.7% on semaglutide 2.4mg (Wegovy).¹⁵ For someone starting at 100 kg, that is about 20 kg versus about 14 kg on average.

There is an important catch in the question itself. Ozempic is semaglutide licensed for type 2 diabetes. It is not a UK weight-loss medicine, and prescribing it privately for weight loss is off-label.¹ The licensed weight-management options are Mounjaro and Wegovy, so the fair comparison is Mounjaro versus Wegovy for UK results. A regulated UK pharmacy will not supply Ozempic for weight loss.

Who each option suits: Mounjaro and Wegovy are both licensed for weight management, and your prescriber decides which suits you, taking account of your health profile, other medicines and tolerance. Wegovy suits adults whose prescriber prefers semaglutide, perhaps because of their history or how they tolerated it before. Both are effective, and the choice is a clinical one, not just a headline number.

02 · Side by side

Ozempic, Wegovy and Mounjaro compared

The table keeps each trial's figures in its own row. Only SURMOUNT-5 compares tirzepatide and semaglutide head to head, so do not read the other rows as a contest.

You can see current doses and prices on the Mounjaro pen page or the Wegovy pen page. First-order prices already include the new-customer discount (code FIRST40), and an automatic £25 reorder discount applies to every future order (code DOSE25).

03 · Deciding

What to weigh up besides the headline number

The average gap is real, but it is an average. Trial averages do not predict your own result, and some people on semaglutide lose more than some people on tirzepatide. Treatment also works alongside a reduced-calorie diet and increased physical activity, not instead of them.²

Three factors usually decide the choice. First, your health profile and other medicines, which a prescriber will review. Second, how well you tolerate each drug; see our guide on which has fewer side effects. Third, your goals, which your prescriber will discuss with you.

Ready to see whether you are suitable? Start your free consultation. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full.

04 · Head-to-head trial

What SURMOUNT-5 actually showed

SURMOUNT-5 is the first large head-to-head trial of tirzepatide and semaglutide 2.4mg for weight loss. It enrolled 751 adults who took one or the other for 72 weeks. Average loss was 22.8 kg on tirzepatide versus 15.0 kg on semaglutide.¹⁵

The threshold results show the difference more clearly than the average does. These are the shares of participants who reached each level of weight loss:

Both are effective, licensed treatments. Which suits you depends on your health profile, tolerance and prescriber advice, not the headline number alone.¹⁵ For a wider look at this question, see which is better, semaglutide or tirzepatide.

05 · Why Ozempic is different

Why "Ozempic vs Mounjaro" is really Mounjaro vs Wegovy

Ozempic and Wegovy both contain semaglutide, but they are licensed for different purposes. Ozempic is licensed in the UK for type 2 diabetes. Wegovy is semaglutide 2.4mg licensed for weight management, with pens at 0.25mg, 0.5mg, 1mg, 1.7mg and 2.4mg once weekly.¹⁸ Titration steps up after at least four weeks and reaches the 2.4mg maintenance dose from week 17.

Because Ozempic is not a UK weight-loss medicine, using it for weight loss is off-label, and a regulated UK pharmacy will not supply it for that purpose.¹ That is why the trial evidence that matters for weight loss is the semaglutide 2.4mg data (Wegovy), compared with tirzepatide.

06 · Mounjaro dose results

How much weight people lost on each Mounjaro dose

Results rise with dose. In SURMOUNT-1, 2,539 adults taking tirzepatide alongside diet and exercise lost on average 15% of body weight on 5mg, 19.5% on 10mg and 20.9% on 15mg over 72 weeks, versus 3.1% with lifestyle changes alone.² For someone starting at 100 kg, 20.9% is about 21 kg.

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%.² These are trial averages, and individual results vary.

Weight loss in trials also came with average improvements in waist size, blood pressure, cholesterol and blood-sugar measures, and most participants with prediabetes returned to normal blood-sugar levels. These are secondary outcomes, not promises.²

07 · Semaglutide trial results

Semaglutide 2.4mg: the STEP 1 results

Semaglutide 2.4mg is an effective treatment in its own right. In STEP 1, adults on semaglutide 2.4mg lost on average 14.9% of body weight over 68 weeks, versus 2.4% on placebo.⁹ In the same trial, 86.4% lost at least 5% of body weight (31.5% on placebo), 69.1% lost at least 10% (12.0%) and 50.5% lost at least 15% (4.9%).

STEP 1 and SURMOUNT-1 were separate trials with different designs, so their numbers should not be set against each other. The fair comparison is SURMOUNT-5.

08 · Tolerability

Results also depend on whether you can stay on treatment

A medicine only works if you can keep taking it. In STEP 1, gastrointestinal side effects 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, versus 3.1% on placebo.⁹

For tirzepatide, the commonest early effects are mild nausea, altered appetite and tiredness in the first days after each injection, and they usually settle.¹³ For more detail, see what has more side effects, Ozempic or Mounjaro. Report any suspected side effect through the Yellow Card scheme.¹⁹

09 · Realistic timelines

How fast do results arrive on either medicine?

Gradually. Weight loss on Mounjaro is gradual by design: the first weeks on 2.5mg are an adjustment phase and losses are usually modest, with most measurable progress building from 5mg onward. Trials measured results at 72 weeks, so think in months, not days.²

A sensible 3-month expectation on a standard titration is mid single digits as a percentage of body weight, with wide individual variation. Slower early progress does not predict failure, because the dose you respond to may still be ahead of you. Plateaus of a few weeks are normal; the answer is to review food intake, protect protein and activity, and ask your prescriber about a step-up, never to double doses or add unlicensed products. For a deeper look at weight-loss performance, see what works better for weight loss.

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

10 · Switching safely

Switching from semaglutide to Mounjaro

If you are on semaglutide and wondering about Mounjaro, there is no licensed direct conversion between the two. Switching is 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, often the 2.5mg starting dose.

Never run two GLP-1 medicines together. Mounjaro must also not be combined with unlicensed "research" peptides such as retatrutide, which has no UK licence, or with compounded copies. Mounjaro's mechanism is also different: tirzepatide activates both GIP and GLP-1 receptors, which helps regulate appetite and slows how quickly the stomach empties.¹

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

12 · NHS and private access

NHS and private access

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.

At EverydayMeds, Mounjaro is supplied through official LillyDirect supply, so you receive genuine KwikPens, and all six doses are in stock. Orders placed by 3pm are dispatched the same day, with free next-day tracked delivery in temperature-controlled packaging. See all weight loss treatments we offer.