How long should I stay on Mounjaro?
How long you stay on Mounjaro depends on your weight loss goals, how well you tolerate the medication, and whether you’re accessing it privately or through the NHS.
The SURMOUNT-1 trial showed that after 72 weeks on Mounjaro, participants lost an average of 20.9% of their body weight, with 94% tolerating the medication well enough to complete the trial.1
The SURMOUNT-4 trial extended this to 88 weeks, showing continued benefits for those who remained on the medication, with an average weight loss of 25.3%.2
Put simply, most people can expect to reach their weight-loss goals within 1-2 years on Mounjaro.
After reaching your goal, you have options: continue on Mounjaro to maintain your results, transition to a lower maintenance dose, or work with your prescriber to come off the medication gradually while focusing on the healthy habits you’ve developed.
What the research tells us
| Duration |
What to expect |
Key consideration |
| 0-12 weeks |
Initial weight loss begins; side effects most common |
Focus on building habits alongside medication |
| 12-36 weeks |
Significant weight loss (average 15-21%) |
Reach maintenance dose; monitor progress |
| 36-72 weeks |
Continued weight loss, approaching plateau |
Evaluate long-term goals with the prescriber |
| 72-88 weeks |
Weight loss plateaus (average 22-26%) |
Continue losing if needed, lower dose option for maintenance, or gradual transition with habit support |
| 88+ weeks |
Maintenance phase for most people |
Same as above |
How long will I continue to lose weight on Mounjaro?
Weight loss with Mounjaro typically plateaus after approximately 18 months (72-88 weeks) of treatment when titrated to the highest dose.
The average weight loss at this point is around 22-26% of starting body weight, though individual results vary. Some people lose 10-15%, while others achieve 30% or more.1,2
A 2025 analysis of the SURMOUNT trials found that the time to reach a weight plateau varied by starting BMI. People with class II or III obesity (BMI 35+) typically took longer to plateau (around 36 weeks) compared to those with lower starting weights (around 24 weeks).3
The amount of weight you lose depends on more than just the medication. The healthy habits you develop while taking Mounjaro, such as eating more protein, moving more, and managing stress, all contribute to your results.
This is why building sustainable habits from day one is so important. The medication creates a window of opportunity where changing your eating patterns feels easier because your appetite is reduced.
Can I stay on a lower maintenance dose?
Yes. Many people who reach their weight-loss goals choose to stay on a lower maintenance dose rather than stop completely or remain on the maximum dose.
Mounjaro has three maintenance doses: 5 mg, 10 mg, and 15 mg. Your prescriber will help you find the dose that maintains your results while minimising any ongoing side effects.
Staying on a lower dose can be a practical middle ground. It helps maintain lower hunger without requiring higher doses and may be easier to tolerate over the long term.
The decision about maintenance dosing should be made with your prescriber based on:
- How much weight you lost
- Whether your appetite has increased at lower doses
- Any ongoing side effects
- Your long-term weight maintenance goals
- Cost considerations (higher doses cost more)
Some people maintain their weight loss on 5 mg or 7.5 mg, while others need 10 mg or 15 mg. There’s no single right answer.
What happens when you stop Mounjaro?
When you stop taking Mounjaro, your appetite will gradually return to its previous levels as the medication clears your system if you haven’t developed healthy habits to manage hunger naturally. This typically occurs over 3-5 weeks because tirzepatide has a half-life of about 5 days.4
The SURMOUNT-4 trial specifically studied what happens when people stop Mounjaro after significant weight loss.2
After 36 weeks on Mounjaro, participants had lost an average of 20.9% of their body weight. They were then split into two groups: one continued on Mounjaro, and one switched to a placebo.
After another 52 weeks (88 weeks total from the start):
- Those who continued Mounjaro lost an additional 5.5%, reaching 25.3% total weight loss
- Those who stopped regained 14% of their body weight, ending at 9.9% total weight loss from baseline
Nearly 90% of those who continued treatment maintained at least 80% of their weight loss, compared to just 16.6% of those who stopped.2
This doesn’t mean stopping Mounjaro leads to complete weight regain. After almost two years, the group that stopped had still lost nearly 10% of their starting weight, which is clinically significant.
However, the trend in this group showed continued weight regain over time, which is why developing sustainable habits while on the medication is so important.
Why weight regain happens
When you stop Mounjaro, several things change:
- Hunger returns: The medication’s effect on appetite-regulating hormones (GLP-1 and GIP) fades
- Food noise comes back: Many people notice that they think about food more often
- Cravings may increase: Particularly for high-calorie foods
- Stomach empties faster: You may feel hungry sooner after meals
This is why the habits you build while taking Mounjaro are crucial. If you’ve developed sustainable eating patterns, regular physical activity, and a healthier relationship with food, you’ll be able to maintain lower hunger levels better.
How to safely come off Mounjaro
If you decide to stop taking Mounjaro, a gradual approach is generally better than stopping suddenly. This gives your body time to adjust and allows you to monitor how your appetite changes at each stage.
Tapering approach
Work with your prescriber to reduce your dose gradually. A typical approach might be:
- Reduce from 15 mg to 10 mg for 4-8 weeks
- Then from 10 mg to 7.5 mg for 4-8 weeks
- Then from 7.5 mg to 5 mg for 4-8 weeks
- Then from 5 mg to 2.5 mg for 4-8 weeks before stopping
At each stage, monitor your hunger levels and eating patterns. If you notice significant increases in appetite or cravings, you may want to stay at that dose longer or discuss options with your prescriber.
Preparing for life after Mounjaro
The best time to prepare for coming off Mounjaro is while you’re still taking it. Focus on:
Protein at every meal: Protein helps you feel full for longer. Aim for 30-40g at each main meal, roughly a palm-sized portion of meat, fish, or plant-based protein like tofu.
Regular eating patterns: Three balanced meals a day help train your hunger hormones to expect food at predictable times.
Physical activity: Regular movement, particularly strength training, helps maintain muscle mass and supports your metabolism.
Understanding your triggers: Use the time when food noise is quieter to identify what drives your eating patterns, whether that’s stress, boredom, social situations, or emotional responses.
On Second Nature, our dietitians and nutritionists help you build these habits from day one, so you’re prepared for life after medication.
NHS vs private prescription duration
There’s an important difference between NHS and private prescriptions when it comes to how long you can take Mounjaro.
NHS prescriptions
NICE approved Mounjaro for obesity management in December 2024, but with significant restrictions on duration and access.5
Current NHS guidance recommends reviewing treatment if less than 5% of body weight has been lost after 6 months on the highest tolerated dose.
The guidance also notes that similar medications (semaglutide and liraglutide) are only recommended for up to 2 years within specialist weight management services.5
Access through the NHS is currently limited and being rolled out in phases over 3 years, with priority given to those with the highest clinical need (BMI 40+ with multiple weight-related conditions).6
Private prescriptions
If you purchase Mounjaro privately, there’s no set time limit. You can continue taking the medication for as long as:
- It remains medically appropriate
- You tolerate it well
- Your prescriber approves continued use
This is one reason many people choose private programmes like Second Nature. You have more flexibility in how long you take the medication and can work with your clinical team to find the approach that works best for you.
Frequently asked questions
Is Mounjaro a lifelong medication?
It can be, but it doesn’t have to be. Some people take Mounjaro long-term to maintain their weight loss, while others use it for 1-2 years to reach their goals and then transition off while keeping their results through healthy habits. There’s no single right approach.
Will I regain all the weight if I stop Mounjaro?
Not necessarily. Research shows that people who stop Mounjaro do tend to regain some weight, but the amount varies significantly.
In the SURMOUNT-4 trial, participants who stopped after 36 weeks still maintained nearly 10% weight loss after another year.2 Developing sustainable habits while on the medication improves your chances of maintaining results.
How long does Mounjaro stay in your system after stopping?
Tirzepatide has a half-life of about 5 days, which means it takes approximately 25-30 days (5 half-lives) for the medication to clear your system fully.4 You’ll likely notice your appetite returning gradually over this period.
Can I stay on a lower dose once I reach my goal weight?
Yes. Many people transition to a lower maintenance dose (5 mg, 7.5 mg, or 10 mg) once they’ve reached their goals. This can help maintain results while reducing costs and minimising any ongoing side effects. Discuss this option with your prescriber.
Should I taper off or stop suddenly?
Tapering is generally recommended. Gradually reducing your dose over several weeks or months gives your body time to adjust and allows you to monitor how your appetite changes at each stage. This approach may also help reduce weight regain.
Can I restart Mounjaro if I regain weight?
Yes, in most cases you can restart Mounjaro if you’ve stopped and subsequently regained weight. You would typically start again at the lowest dose (2.5 mg) and titrate up, following the same schedule as when you first started. Discuss this with your prescriber.
What’s the difference between NHS and private prescription duration?
NHS prescriptions for similar weight-loss medications are typically limited to 2 years in specialist weight-management services.
Private prescriptions have no set time limit; you can continue as long as it’s medically appropriate and approved by your prescriber.
How do I determine the appropriate maintenance dose for me?
The right maintenance dose depends on several factors: how well you maintain your weight at different doses, any side effects you experience, and your long-term goals. Your prescriber will help you find the balance that works for you, often through trial and adjustment.
Take home message
There’s no time limit on how long you can take Mounjaro if you’re accessing it privately. Most people reach their weight loss goals within 1-2 years, after which they can choose to continue on a maintenance dose or transition off the medication.
The SURMOUNT trials show that continuing Mounjaro maintains and even increases weight loss, whereas stopping leads to some regain.
However, the degree of regain varies, and people who develop sustainable habits while on the medication tend to maintain better results.
The key isn’t just how long you take Mounjaro, but what you do with that time. Use it as an opportunity to build eating patterns, activity habits, and coping strategies that will support your weight over the long term.
Whether you’re planning to stay on Mounjaro for years or use it as a bridge to lifestyle changes, having the right support makes all the difference.
Second Nature's Mounjaro and Wegovy programmes
Second Nature provides Mounjaro or Wegovy as part of our Mounjaro and Wegovy weight-loss programmes.
Why choose Second Nature over other medication providers, assuming you're eligible?
Because peace of mind matters.
We've had the privilege of working with the NHS for over eight years, helping people across the UK take meaningful steps toward a healthier, happier life.
Our programmes are designed to meet people where they are, whether that means support with weight loss through compassionate one-to-one health coaching, or access to the latest weight-loss medications (like Mounjaro and Wegovy) delivered alongside expert care from a multidisciplinary team of doctors, psychologists, dietitians, and personal trainers.
At the heart of everything we do is a simple belief: real, lasting change comes from building better habits, not relying on quick fixes. We're here to support that change every step of the way.
With over a decade of experience, thousands of lives changed, and a long-standing record of delivering programmes used by the NHS, we believe we're the UK's most trusted weight-loss programme.
We hope to offer you something invaluable: peace of mind, and the support you need to take that first step.
References
- Jastreboff, A.M., et al. (2022). Tirzepatide Once Weekly for the Treatment of Obesity. New England Journal of Medicine, 387(3), 205-216.
- Aronne, L.J., et al. (2024). Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial. JAMA, 331(1), 38-48.
- Horn, D.B., et al. (2025). Time to weight plateau with tirzepatide treatment in the SURMOUNT-1 and SURMOUNT-4 clinical trials. Clinical Obesity.
- Eli Lilly and Company. (2024). Mounjaro (tirzepatide) Summary of Product Characteristics.
- National Institute for Health and Care Excellence. (2024). Tirzepatide for managing overweight and obesity (TA1026).
- NHS England. (2025). Interim commissioning guidance: implementation of NICE TA1026 for tirzepatide.
