6 Months on GLP-1: What Really Happens (October 2026)

01 · The core answer

How much weight can you lose in 6 months on a GLP-1?

It depends on your dose, your starting weight and how you eat and move, and trials measured results at 72 weeks rather than six months. The main Mounjaro figures come from 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

Those are trial averages and individual results vary. Treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.² To see what a percentage means in practice: for someone starting at 100 kg, 20.9% is about 21 kg, and 15% is about 15 kg. That is the result at 72 weeks, not at six months.

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.² If you want to see how the early stage looks, our one-month before and after guide covers it, and our page on Mounjaro after six months goes deeper on that specific drug.

02 · Planning the cost

What does six months on Mounjaro cost?

The Mounjaro pen is priced per dose, and each pen lasts four weeks. The standard 2.5mg pen costs £169.99, 5mg costs £218.99, 7.5mg costs £279.99 and 10mg costs £290.99. Your first 2.5mg pen costs £129.99 with code FIRST40, and every later order is £25 off the standard price (code DOSE25).

If you step up after 4 weeks on each dose, your first four pens (2.5mg to 10mg) cost £959.96 at standard prices. A first year of 13 pens 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. A new customer's first order is £40 less and every later order £25 less. The 12.5mg pen is £319.99 and the 15mg pen is £329.99. Switching to us at a higher dose? Your first 15mg order is £289.99.

Across the UK pharmacies we track, the cheapest and dearest Mounjaro pens range from £143.96 to £339.00 per month depending on dose and provider (checked 10 October 2026). Consultation with us is free, and the price shown is the price paid.

03 · Next step

Starting, or already six months in?

Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full. If you are already on treatment and wondering whether six months is enough, our guide to whether six months on Mounjaro is enough covers that decision. Questions about buying several months at once are answered in our guide to buying six months of Mounjaro. Start your free consultation when you are ready.

04 · Month-by-month pace

What six months usually looks like on the dose ladder

Mounjaro comes in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg, in a once-weekly KwikPen.¹ By around six months, most people on a standard titration have moved beyond the starter dose and are close to, or at, the dose they will stay on.

That matters because the highest average trial results were at the higher doses. The 2.5mg weeks are an adjustment phase, and most measurable progress builds from 5mg onward.² Three months in, most people are still on the lower rungs, so losses at that point are modest compared with the headline figures. A sensible 3-month expectation 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. Think in months, not days, and judge progress by trend rather than individual weigh-ins.

05 · Plateaus at six months

Hitting a plateau around six months

A plateau of a few weeks is normal and expected, because the body adapts to a lower weight. Weight loss on Mounjaro is not linear, so a stall does not mean the medicine has stopped working.

Within the licence, the sensible responses are:

• Review your food intake honestly, since portions drift back up over time.
• Protect protein and activity.
• Check the basics: sleep and alcohol.
• Ask your prescriber whether a dose step-up is appropriate, if you are not yet at maximum.

A plateau is not a reason to double doses or add unlicensed products. Our prescribing team handles dose changes through ongoing monthly reviews. People weighing up how long to continue can read our guide on whether you can take Mounjaro for six months.

Treatment response is also formally reviewed. 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.⁴

06 · Is six months safe?

Is it safe to take a GLP-1 for six months?

Mounjaro is a licensed prescription medicine for weight management in adults, used alongside a reduced-calorie diet and increased physical activity.¹ Safety depends on whether it suits you, which a prescriber assesses from your BMI, medical history and current medicines.

The commonest early effects are mild nausea, altered appetite and tiredness in the first days after each injection, and these usually settle. The most common side effects are digestive: more than 1 in 10 people have nausea, diarrhoea, vomiting, constipation and abdominal discomfort. Side effects are most likely when starting treatment or moving up a dose.¹³ If a new symptom worries you, speak to your prescriber, and you can report suspected side effects through the MHRA Yellow Card scheme.¹⁹

Our monthly clinical reviews re-check suitability, and repeat orders are never auto-shipped. Buy only from a registered pharmacy; you can check ours on the GPhC register (registration 9012878). Anyone offering to supply without a consultation or prescription should be avoided.

07 · Who is eligible

Who can start, and what about the NHS?

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 such as high blood pressure, high cholesterol, obstructive sleep apnoea, cardiovascular disease, prediabetes or type 2 diabetes.¹

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.

If you are comparing options, see all weight loss treatments we offer, including the Wegovy pen. Wegovy's dose ladder runs 0.25mg, 0.5mg, 1mg, 1.7mg and 2.4mg, with four weeks on each of the first four steps and the 2.4mg maintenance dose starting from week 17.¹⁸

08 · Beyond the scales

Signs of progress beyond the scales

Early signs that treatment is working are usually appetite changes: feeling fuller sooner and less hungry between meals. This follows from how tirzepatide activates the GIP and GLP-1 receptors, helping regulate appetite and slowing how quickly the stomach empties.¹

Early loss includes water weight, so the trend over weeks matters more than any single weigh-in. In trials, weight loss on tirzepatide 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.² These are trial-average secondary outcomes, not promises, but they are why prescribers talk about weight management as health management rather than appearance.

Waist measurement, clothes fit and blood pressure checks are useful alongside the scales. Our free GLPTrackr app helps you log these over time.

09 · Big targets

Can you lose several stone in six months?

Setting a large target for six months is a common goal, but trial results were measured at 72 weeks. The SURMOUNT-1 results are 72-week averages, and half of participants on 10mg and 57% on 15mg lost at least 20% of their body weight at that point.² At 72 weeks, 85% of participants on 5mg, 89% on 10mg and 91% on 15mg had lost at least 5%.

Trial averages do not predict your own result. The better plan is to agree a realistic pace with your prescriber, track the trend, and treat the dose ladder as the route rather than rushing it. Taking more than prescribed is unsafe and outside the licence; a plateau is not a reason to double doses.

10 · Age and looking younger

Age, appearance and weight loss

If you are concerned about how your age, menopause, medicines or health conditions may affect weight loss, raise it in your consultation or monthly review so a prescriber can look at your whole picture. Our page on weight loss injections at six months and the overview of GLP-1 treatment at six months offer further reading.

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 · How ordering works

How ordering with EverydayMeds works

Ordering takes three steps, starting with a free online consultation.

• Free online consultation: a short health questionnaire, no charge and no obligation.
• Prescriber review: a GPhC-registered prescriber reviews it. 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: we supply genuine KwikPens through official LillyDirect supply. Same-day dispatch applies when ordered by 3pm, with free next-day tracked delivery in temperature-controlled packaging. Saturday delivery is £14.99.

Needles, a sharps bin and injection guidance come with every order. Klarna and pay-monthly options are available, with no subscription lock-in. Compare dose options on the Mounjaro pen page. Support runs Monday to Friday, 9am to 5pm on 0333 207 0413. Another useful read is how six-in-one GLP-1 products compare.