There is no fixed course for Mounjaro (tirzepatide). The UK licence covers weight management, including weight loss and weight maintenance. [1] It sets no end date for adults. [1]
Its one decision point on continuing comes 6 months after you reach the highest dose you tolerate. [1] A licence is a medicine’s UK approval. Its rules sit in the Summary of Product Characteristics (SmPC), the document the regulator approves for each medicine.
The regulator is the Medicines and Healthcare products Regulatory Agency (MHRA). This article sets out what the licence, the NHS and the trials say about staying on, pausing and stopping.
What does the licence say about how long you stay on treatment?
The licence sets no maximum duration for adults. [1] Its licensed use names weight maintenance as part of treatment, alongside weight loss. [1] It also sets no weight at which treatment ends. [1]
Mounjaro is licensed as an addition to a reduced-calorie diet and increased physical activity. [1] It is for adults with a body mass index (BMI) of 30 or more. [1] It also covers a BMI of 27 to under 30 with at least one weight-related condition. [1]
BMI is your weight against your height.
When does the licence require a decision on continuing?
The rule applies if you have been unable to lose at least 5% of your initial body weight. [1] The clock is 6 months after titrating to your highest tolerated dose. [1] Titrating means stepping the dose up.
A decision is then required on whether to continue. [1] The licence says that decision weighs the benefit and risk for you as an individual. [1] So the clock starts when you reach your highest tolerated dose, not when you start treatment. [1]
NICE is the National Institute for Health and Care Excellence. Its guidance for the NHS carries the same rule. [2] The NHS in England must fund tirzepatide where NICE recommends it. [2]
Outside that review, the leaflet says to use the medicine exactly as your doctor or pharmacist has told you. [3] How long you continue is a decision made with your clinician.
Does reaching a maintenance dose mean treatment is ending?
No. A maintenance dose is the dose you stay on once the build-up is complete. The name describes a dose level, not a length of treatment.
For Mounjaro the licence names 5, 10 and 15 mg once a week as the recommended maintenance doses. [1] Dose increases are 2.5 mg steps after at least 4 weeks on the current dose, and the licence says “if needed”. [1] So staying longer on a dose is within the licence.
The week-by-week article sets out each dose step and what to expect at it.
Does the NHS set a time limit on treatment?
No. NICE’s guidance sets no maximum treatment duration for tirzepatide on the NHS. [2] NHS England’s guidance says the medicine has no set stopping rule or maximum treatment period. [4]
It says the decision to continue is made case by case, by a trained healthcare professional in consultation with the patient. [4] In its cost-effectiveness analysis, NICE’s committee did not apply a 2-year stopping rule for tirzepatide. [2]
NHS access criteria are narrower than the licence. The week-by-week article sets them out.
NICE also sets a decision point: less than 5% of the initial weight lost after 6 months on the highest tolerated dose. [2] That is the licence’s rule. [1] For private treatment, the licence and your clinician’s reviews apply. [1] [5]
What do the longest trials show about continued treatment?
In the longest trial, weight loss was sustained for 176 weeks on continued treatment in adults with obesity and prediabetes. [6] That is about 3 years and 4 months. Prediabetes means blood sugar above the normal range but below the diabetes threshold.
In the main 72-week trial, weight loss occurred early and continued throughout. [1] A later analysis found the loss was fastest in the first 24 weeks. [7]
SURMOUNT-1 followed 2,539 adults with obesity or overweight and no diabetes for 72 weeks. [1] The results article gives the figures at each dose. This section covers how long the loss continued.
When did weight loss level off in the trials?
In a post hoc analysis of SURMOUNT-1, the median time to a plateau was between 24.3 and 36.1 weeks. [7] The median is the middle value. Post hoc means the analysis was decided after the trial.
The analysis covered people who stayed on treatment and lost at least 5%. [7] It defined a plateau as a change of less than 5% over 12 weeks and every later 12-week interval. [7] Plateaus came later in people with a higher starting BMI. [7]
By week 72, between 87.6% and 90.2% had reached one. [7] The analysis also covered SURMOUNT-4. There, around 12% of the 259 people who stayed on tirzepatide had not reached a plateau by week 88. [7]
Eight of the ten authors were manufacturer employees. [7] Average trial results are not a prediction of individual results.
What the 3-year extension found
At 176 weeks the published mean weight change was 12.3% down on 5 mg, 18.7% on 10 mg and 19.7% on 15 mg. [6] On placebo it was 1.3% down. [6] A placebo is an injection with no active medicine.
The published summary does not say whether those figures count people who stopped early. [6] The analysis covered the 1,032 SURMOUNT-1 participants who had prediabetes at the start. [6] Their assigned treatment or placebo ran for 176 weeks. [6]
Treatment then stopped for 17 weeks. [6] The published summary gives no weight figure for the weeks off treatment. [6]
That population had obesity and prediabetes, so it is not the whole weight-management population. [6] The manufacturer funded the trial. [6] Average trial results are not a prediction of individual results.
No trial has yet reported whether tirzepatide changes rates of illness and death in the weight-management population as a whole. One is under way in adults with obesity, with completion expected in October 2027. [8]
What happens to your weight when you stop?
In the trial designed to answer this, people who stopped after 36 weeks regained 14.0% of their body weight over the next year. [9] They had lost 20.9% while on treatment, and they ended 9.9% below their starting weight. [9] Those who continued lost a further 5.5%. [9]
Those figures count everyone randomised (allocated at random to a group), including people who stopped the trial treatment early. [9] A 2026 review of 37 studies put regain after tirzepatide or semaglutide at about 0.8 kg a month. [10] Results varied widely between people. [11] [10]
The regain figures at a glance
| Study | Design | After stopping |
|---|---|---|
| SURMOUNT-4 (2024) | 670 people who had reached 10 or 15 mg over 36 weeks continued or switched to placebo for 52 weeks. Diet and activity counselling continued in both groups. [9] | The placebo group regained 14.0% of body weight, counting everyone randomised. It ended 9.9% below its starting weight. The continued group lost a further 5.5%, ending 25.3% below. [9] |
| SURMOUNT-4 post hoc analysis (2026) | The 308 people switched to placebo who had lost at least 10% on treatment. [11] | 82.5% regained at least a quarter of the lost weight within the year. About 1 in 2 regained at least half. Almost 9% ended above their starting weight, and 17.5% regained less than a quarter. [11] |
| BMJ review (2026) | 37 studies and 9,341 participants across several weight-management medicines. SURMOUNT-4 was among them. [10] | 0.8 kg a month after tirzepatide or semaglutide, 9.9 kg in the first year. Projected return to starting weight at about 1.5 years. [10] |
What the SURMOUNT-4 trial found
SURMOUNT-4 was designed to answer this question. 783 people started tirzepatide, stepping up over 36 weeks to 10 or 15 mg. [9] The 670 who reached one of those doses had lost a mean (average) of 20.9%. [9]
They were randomised: 335 continued and 335 switched to placebo for 52 weeks. [9] Both groups kept counselling for a diet 500 kcal a day below their needs and at least 150 minutes of physical activity a week. [9] Dose changes were not allowed after randomisation. [9]
Over the next 52 weeks the continued group lost a further 5.5%. [9] The placebo group regained 14.0% of its body weight, counting everyone randomised. [9] The gap between the groups was 19.4 percentage points. [9]
A percentage point is the gap between two percentages. By week 64 the placebo group was already up 10.0%. [9] That was 28 weeks after the switch.
How much of the lost weight was kept at week 88?
At week 88, 89.5% of the continued group had kept at least 80% of the weight lost in the first 36 weeks. [9] That count includes everyone randomised. [9] In the placebo group the figure was 16.6%. [9]
Even so, the placebo group’s mean weight at week 88 was still 9.9% below its starting level. [9] The authors call that a substantial reduction but say much of the initial improvement in cardiometabolic risk factors had been reversed. [9]
Cardiometabolic measures are markers such as blood pressure, blood sugar and cholesterol. The trial was 70.6% women and excluded people with diabetes. [9]
The limits matter. Everyone randomised had tolerated 10 or 15 mg, which the authors say may be a subgroup of the general population. [9] Intensive behavioural therapy was not tested. [9]
The manufacturer sponsored the trial and was involved in its design, analysis and reporting. [9] Six of the twelve named authors gave the manufacturer as their affiliation. [9] Average trial results are not a prediction of individual results.
How much the regain varied
A 2026 post hoc analysis looked at the 308 people switched to placebo who had lost at least 10% on treatment. [11] Most regained weight despite continued lifestyle counselling, but the amount varied widely. [11]
82.5% regained at least a quarter of what they had lost within the year. [11] About 1 in 2 regained at least half, and 1 in 4 regained at least three quarters. [11] Almost 9% ended above their starting weight. [11]
At the other end, 17.5% regained less than a quarter and about 4% kept losing weight. [11] The more weight people regained, the further their waist, systolic blood pressure, non-HDL cholesterol and HbA1c moved back. [11] HbA1c is a blood test of average blood sugar over about 3 months.
Blood sugar measures began to move back within 16 weeks of stopping. [11] In people who regained less than a quarter, waist size, non-HDL cholesterol and fasting insulin showed no significant change from the switch. [11] Non-HDL cholesterol is total cholesterol minus the HDL (high-density lipoprotein) type.
The analysis was 71.1% women. [11] Six of the ten authors were manufacturer employees. [11] Average trial results are not a prediction of individual results.
What a 2026 review of 37 studies found
A systematic review pools the results of many trials. One appeared in the medical journal the BMJ in January 2026. It pooled 37 studies with 9,341 participants across weight-management medicines. [10]
SURMOUNT-4 was among them. [10]
After tirzepatide or semaglutide, regain ran at 0.8 kg a month. [10] The review estimated 9.9 kg regained in the first year. [10] Its main text gives no tirzepatide-only figure. [10]
The authors projected a return to starting weight about 1.5 years after stopping. [10] Across all the medicines pooled, they projected cardiometabolic markers to return to their starting levels within 1.4 years. [10] Data were insufficient to analyse those markers after tirzepatide or semaglutide. [10]
They also noted that the figures are averages and that a small proportion of people kept their weight off. [10] The review had only eight studies of the newer medicines, with at most 12 months of follow-up after stopping. [10] The longer figures are projections, not observations. [10]
Average trial results are not a prediction of individual results.
What happens in the body after the last dose?
Tirzepatide has a half-life of approximately 5 days. [1] A half-life is the time for the blood level to fall by half. The licence gives no figure for how long the medicine stays in the body after the last dose. [1]
Tirzepatide is a GIP and GLP-1 receptor agonist. [1] GIP is glucose-dependent insulinotropic polypeptide and GLP-1 is glucagon-like peptide-1, both gut hormones. A receptor agonist is a medicine that acts on the same receptors as the hormone.
Both receptors are found in the areas of the brain that regulate appetite. [1]
In clinical studies tirzepatide reduced appetite by increasing feelings of fullness, decreasing hunger and decreasing food cravings. [1] The leaflet says it primarily works by regulating your appetite. [3] No trial in this article measured appetite after stopping.
The BMJ review’s authors say these medicines work by reducing hunger and increasing satiety (fullness). [10] They add that conscious diet and activity effort is the only recourse after stopping. [10] They describe obesity as a chronic and relapsing condition. [10]
Do diet and exercise changes stop the weight coming back?
Not on average, in the trials so far. In SURMOUNT-4 both groups kept lifestyle counselling throughout, and the group that switched to placebo still regained 14.0% of its body weight. [9] The BMJ review found no evidence that behavioural support after stopping changed the rate of regain. [10]
The review did not find that more support during treatment slowed regain afterwards either. [10] Its authors note that the NICE quality standard recommends support after stopping. [10] They found no evidence that such support leads to slower regain. [10]
What happened after an intensive lifestyle programme
SURMOUNT-3 started with a 12-week intensive lifestyle programme. [12] It had eight counselling sessions and at least 150 minutes of activity a week. [12]
Of 806 people who started it, 579 lost at least 5% and were randomised to tirzepatide or placebo for 72 weeks. [12]
Counselling continued every 12 weeks, with monthly reinforcement of the diet and activity goals. [12] The placebo group regained 2.5% of its body weight over the 72 weeks, counting everyone randomised. [12] At week 72, 43.8% of that group had kept at least 80% of their lifestyle-programme loss. [12]
The trial was 37.1% men and excluded people with diabetes. [12] The authors suggest the quarterly counselling frequency could explain the placebo group’s regain. [12] They report that many of the cardiometabolic improvements from the programme reverted towards baseline in the placebo group. [12]
The trial ran in North and South America with a predominantly white population. [12] People who did not respond to the lifestyle programme were not randomised. [12] The manufacturer funded it and employed five of the authors. [12]
Average trial results are not a prediction of individual results.
What one exercise trial found
One Danish trial points the other way, with limits. After an 8-week diet that cut a mean of 13.1 kg, people were allocated to one of four groups for a year. [13]
- a different GLP-1 medicine
- supervised exercise
- both together
- placebo
Treatment and exercise then stopped for a year. [13]
Regain over that year was 6.0 kg larger after the medicine alone than after supervised exercise. [13] People who had done both ended 5.1 kg lower than the medicine-alone group. [13] That advantage did not meet the trial’s pre-set statistical threshold. [13]
Only 109 people attended the follow-up, and they had responded better than those who did not. [13] The exercise was four monitored sessions a week, two of them supervised vigorous group sessions. [13] The trial used a different medicine, so the finding does not transfer directly to tirzepatide.
Average trial results are not a prediction of individual results.
So structured exercise may blunt regain. [13] It has not been shown to prevent it. The plateau article covers what helps when weight loss stalls.
Can you pause treatment and restart later?
The licence covers missed doses, not planned breaks. A missed dose is taken within 4 days. [1] [3] If more than 4 days have passed, it is skipped and the next dose is taken on the usual day. [1] [3]
The licence has no sentence on restarting at a lower dose after missed doses. [1] The week-by-week article covers missed doses and dose changes in detail.
No trial in this article tested planned breaks. The BMJ review lists intermittent treatment as a question for further research, not a finding. [10]
The MHRA says to talk to your prescriber before making any change to your treatment. [5] Whether a pause is right for you is a decision for your clinician. So is how you restart.
Do you have to stop before surgery or sedation?
Not as a rule. The licence does not instruct stopping before a procedure. [1] The medicine delays stomach emptying. [1]
Cases of pulmonary aspiration have been reported in people on GLP-1 receptor agonists under general anaesthesia or deep sedation. [1] Aspiration means stomach contents entering the airways and lungs. [5] So the licence says the increased risk of food or drink remaining in the stomach should be considered before such procedures. [1]
The leaflet says to tell your doctor if you are due to have surgery under anaesthesia. [3] The MHRA says to inform your healthcare team and the anaesthetist before the procedure. [5] Pre-procedure instructions and the anaesthetic technique may need to change. [5]
The MHRA’s advice is to continue your prescribed medicine as usual and not to stop without first discussing it with your doctor. [5]
When does the licence say treatment must stop?
For men, the licence names one situation in which tirzepatide is stopped: suspected pancreatitis. Pancreatitis is inflammation of the pancreas. If it is suspected, tirzepatide is discontinued. [1]
If the diagnosis is confirmed, it is not restarted. [1] Its symptoms include persistent, severe abdominal pain. [1] The licence says to seek immediate medical attention if they occur. [1]
The MHRA adds that the pain may spread to the back and may come with nausea and vomiting. [14] The leaflet says to stop the medicine and seek urgent help for severe, persistent pain in the stomach area. [3]
The leaflet gives the same instruction for a severe allergic reaction. [3] The signs include breathing problems or rapid swelling of the lips, tongue or throat. [3]
These are safety rules set by the licence and the leaflet. Everything else about stopping is a decision between you and your clinician. [3]
How does HeMed fit in?
HeMed starts with a blood test. We measure 10 metabolic markers across four systems from a needle-free blood test at home.
A clinician reviews your blood test first. If they approve treatment, we deliver it the next working day, discreetly packaged, with delivery included in your plan.
A weekly in-app check-in, reviewed by clinicians, so your plan can be adjusted when it needs to be. A retest every 6 months shows what’s actually changing.
Reaching your goal weight does not end your plan by itself. You and your clinician decide what happens next at your regular review.
Mounjaro is a prescription medicine for weight management. Whether it’s right for you is a clinical decision, made from your health information and your baseline blood test.
Frequently asked questions
Is there a maximum time you can stay on treatment?
The licence sets no maximum duration for adults. It requires a decision on whether to continue if you have not lost at least 5% of your starting weight. The clock is 6 months after you reach your highest tolerated dose.
On the NHS, NICE sets no maximum treatment period for tirzepatide either. NHS England’s guidance says the decision to continue is made case by case with your healthcare professional.
How much weight comes back after stopping?
In the SURMOUNT-4 trial, people who switched to placebo after 36 weeks regained 14.0% of their body weight over the next year. They had lost 20.9% on treatment and ended 9.9% below their starting weight. Those figures count everyone randomised, and diet and activity counselling continued throughout.
The trial was 70.6% women and excluded people with diabetes, and everyone randomised had tolerated 10 or 15 mg. Results varied widely: in a post hoc analysis, 17.5% regained less than a quarter of their loss and almost 9% ended above their starting weight. Average trial results are not a prediction of individual results.
Can you take a break and restart later?
The licence covers missed doses, not planned breaks. A missed dose is taken within 4 days. If more than 4 days have passed, it is skipped and the next dose taken on the usual day.
The licence has no sentence on restarting at a lower dose after missed doses. No trial in this article tested planned breaks. Talk to your clinician before any change to your treatment.
Do you have to stop before an operation?
The licence does not say to stop. It says the risk of food or drink remaining in the stomach should be considered before general anaesthesia or deep sedation.
Tell your healthcare team and the anaesthetist that you take the medicine. The MHRA’s advice is to continue as prescribed and not to stop without first discussing it with your doctor.
Does exercise stop the weight coming back?
Not in the trials on average. In SURMOUNT-4 both groups kept diet and activity counselling, and the group that stopped still regained weight. A 2026 review found no evidence that support after stopping slowed regain.
One Danish trial of a different GLP-1 medicine found less regain after supervised exercise. It was small: only 109 people attended the follow-up, and the combination group’s advantage did not meet the pre-set statistical threshold.
Does the licence set a weight at which treatment ends?
No. The licence names weight maintenance as part of treatment and sets no weight at which it ends. Its one decision point is the review 6 months after you reach your highest tolerated dose.
In the trials, weight regain followed stopping on average even where diet and activity counselling continued. Results varied between people. What happens next is a decision to make with your clinician at your regular review.
How long does the medicine stay in your body after the last dose?
Tirzepatide has a half-life of approximately 5 days, which is what allows once-weekly dosing. The licence gives no figure for how long it remains in the body after the last dose.
No trial in this article measured appetite after stopping. The regain figures above describe weight over the year after treatment ended.
HeMed provides clinician-led weight management. Treatment is prescription-only and is prescribed only where a clinician decides it is suitable. This page is general health information, not medical advice. If you are worried about symptoms, speak to your GP, or use NHS 111.
Next step: see what the HeMed blood test measures.
Sources (14)
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- Eli Lilly, Mounjaro KwikPen Patient Information Leaflet, sections 1 to 4 (last revised August 2026). electronic medicines compendium. medicines.org.uk/emc/product/15481/pil. Accessed 10 November 2026.
- NHS England, “Interim commissioning guidance: implementation of the NICE technology appraisal TA1026 and the NICE funding variation for tirzepatide (Mounjaro) for the management of obesity”, section “Reviewing and stopping prescribing” (first published 27 March 2025, updated 2 April 2026). england.nhs.uk/long-read/interim-commissioning-guidance-nice-ta1026-tirzepatide. Accessed 10 November 2026.
- MHRA, “GLP-1 medicines for weight loss and diabetes: what you need to know”, updated 5 February 2026. gov.uk/government/publications. Accessed 10 November 2026.
- Jastreboff AM et al., “Tirzepatide for Obesity Treatment and Diabetes Prevention” (the SURMOUNT-1 three-year results), New England Journal of Medicine 2025;392(10):958 to 971 (abstract; full text not accessed). doi.org/10.1056/NEJMoa2410819. Accessed 10 November 2026.
- Horn DB et al., “Time to weight plateau with tirzepatide treatment in the SURMOUNT-1 and SURMOUNT-4 clinical trials”, Clinical Obesity 2025;15(3):e12734. doi.org/10.1111/cob.12734. Accessed 10 November 2026.
- ClinicalTrials.gov, NCT05556512, “A Study of Tirzepatide (LY3298176) on the Reduction on Morbidity and Mortality in Adults With Obesity” (SURMOUNT-MMO), registry record as shown on 10 November 2026 (status active, not recruiting; no results posted). clinicaltrials.gov/study/NCT05556512. Accessed 10 November 2026.
- Aronne LJ et al., “Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial”, JAMA 2024;331(1):38 to 48. doi.org/10.1001/jama.2023.24945. Accessed 10 November 2026.
- West S et al., “Weight regain after cessation of medication for weight management: systematic review and meta-analysis”, BMJ 2026;392:e085304 (published 7 January 2026). doi.org/10.1136/bmj-2025-085304. Accessed 10 November 2026.
- Horn DB et al., “Cardiometabolic Parameter Change by Weight Regain on Tirzepatide Withdrawal in Adults With Obesity: A Post Hoc Analysis of the SURMOUNT-4 Trial”, JAMA Internal Medicine 2026;186(2):157 to 167. doi.org/10.1001/jamainternmed.2025.6112. Accessed 10 November 2026.
- Wadden TA et al., “Tirzepatide after intensive lifestyle intervention in adults with overweight or obesity: the SURMOUNT-3 phase 3 trial”, Nature Medicine 2023;29(11):2909 to 2918. doi.org/10.1038/s41591-023-02597-w. Accessed 10 November 2026.
- Jensen SBK et al., “Healthy weight loss maintenance with exercise, GLP-1 receptor agonist, or both combined followed by one year without treatment: a post-treatment analysis of a randomised placebo-controlled trial”, EClinicalMedicine 2024;69:102475. doi.org/10.1016/j.eclinm.2024.102475. Accessed 10 November 2026.
- MHRA Drug Safety Update, “GLP-1 receptor agonists and dual GLP-1/GIP receptor agonists: strengthened warnings on acute pancreatitis, including necrotising and fatal cases”, 29 January 2026. gov.uk/drug-safety-update. Accessed 10 November 2026.
Numbered markers in the page text link to these entries. Statistics describe populations, not any one person’s results.
Published 10 November 2026.