Mounjaro timeline: what to expect

New weight loss medications are changing the way we approach obesity treatment. Mounjaro is the latest to hit the UK, having been approved by the MHRA in November 2023. Like Wegovy, it works by making you feel fuller for longer to help you better regulate your appetite.

Studies suggest it’s the most effective weight loss medication yet. Mounjaro patients can expect to lose around 21% of their starting body weight over the course of 18 months.

But that weight loss doesn’t happen straight away, and can only be sustained if you’ve incorporated healthier habits into your lifestyle. Here’s what you can expect from each month of a typical Mounjaro treatment plan.

Mounjaro timeline

The first month you take Mounjaro is the time for your body to get used to the medication and for you to start incorporating healthier habits into your life: a more balanced diet, regular physical activity, well-managed stress levels, better quality sleep.

Over the next few months you should start to experience more weight loss as your body responds to the treatment. You should be able to control your cravings, hold in your hunger pangs and generally regulate your appetite more effectively.

After 18 months, you can expect to lose around 21% of your starting body weight. By now, things like regular exercise and healthy eating habits should be part of your everyday routine.

Here’s a monthly breakdown of what to expect from Mounjaro. Remember that the expected weight loss and dose every month is based on trial data, and your results may be different.

Month 1

Dose: 2.5mg

Month 2

Dose: 5mg | Expected weight loss: 6% body weight*

Month 3

Dose: 7.5mg | Expected weight loss: 9% body weight*

Month 4

Dose: 10mg | Expected weight loss: 11% body weight*

Month 5

Dose: 12.5mg | Expected weight loss: 12% body weight*

Month 6 onwards

Dose: 15mg | Expected weight loss after 18 months: 21% body weight*

*Based on tirzepatide over 72 weeks. Jastreboff, A. M., Aronne, L. J., Ahmad, N. N., Wharton, S., Connery, L., Alves, B., Kiyosue, A., Zhang, S., Liu, B., Bunck, M. C., Stefanski, A., & the SURMOUNT-1 Investigators. Tirzepatide once weekly for the treatment of obesity. The New England Journal of Medicine (2022)

The numan take

Weight loss doesn’t happen overnight, and it could take up to 18 months to get the results you’re looking for from Mounjaro. You can expect to lose 6% of your body weight after two months, 9% after three months, and 11% after four months. But by the 18-month mark, Mounjaro patients experience around 21% weight loss. But be prepared - you’ll need to incorporate healthier habits into your lifestyle for the weight to stay off in the long term.