Can a 15 Year Old Take Mounjaro for Weight Loss? (October 2026)

01 · The answer

Is Mounjaro an option at 15?

No. Mounjaro is the brand name for tirzepatide, a once-weekly injection that in the UK is licensed for weight management in adults and for type 2 diabetes.¹ Nothing in that licence covers weight loss in a 15-year-old, so a prescriber could not suitably supply it.

If you are older, see our guides on tirzepatide at 16, weight loss injections at 16 and Mounjaro at 18. Younger? Read about weight loss injections at 13.

02 · Next steps

What can a 15-year-old do instead?

The first step is to speak to a GP. They can look at the whole picture of health and growth, and refer to a specialist service where that is appropriate. NHS access to Wegovy runs through specialist weight-management services; ask your GP.

Do not buy injections, supplements or "nature's Ozempic" products for a teenager. Low-cost supplements come with no clinical oversight, and dramatic weight-loss claims are not a reason to trust them. Anyone offering to supply a prescription medicine without a consultation or prescription is a warning sign; the MHRA runs counterfeit medicine alerts.⁷

03 · For adults

If you are an adult asking for yourself

Adults with a BMI of 30 or above, or between 27 and 30 with a weight-related condition, may be suitable, and a prescriber assesses BMI, history and current medicines.¹ Our free consultation is reviewed by a GPhC-registered prescriber. The starting 2.5mg Mounjaro pen has a standard price of £169.99 per month, and all six doses are in stock. You can compare every option in our weight loss treatments guide.

04 · Why the licence matters

Why the adult licence matters

A licence sets out who a medicine has been assessed for. Mounjaro's weight-management licence is for 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

It is also meant to be used alongside a reduced-calorie diet and increased physical activity.¹

05 · What the adult trials show

What the adult trial evidence says

In 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 These are trial averages and individual results vary.

This is adult evidence only. It cannot show how a teenager would respond, because the licence covers adults.

06 · NHS access

NHS access for adults

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 primary-care rollout began in June 2025 with the highest-need groups first.⁴⁶ This is the adult pathway; for a teenager, the GP is the route.

07 · Reporting side effects

Safety and reporting

If anyone has taken a prescription medicine that was not prescribed for them, speak to a GP or pharmacist. If they feel very unwell, get medical help straight away. Suspected side effects can be reported through the Yellow Card scheme.¹⁹ Adults curious about early results can read our Mounjaro before and after at one month guide.