ENGLAND — NHS England began incentivising general practitioners to prescribe tirzepatide, sold as Mounjaro, for weight loss to eligible patients in April 2026. The move expanded access to a drug that had been available from NHS specialist weight-loss clinics in England and Wales since March 2025, and from specialist clinics in Scotland under limited circumstances.

Since June 2025, some GPs in England have offered Mounjaro to NHS patients with a body mass index of at least 40, or at least 37.5 for those from minority ethnic backgrounds, who also have at least four of the following conditions: type 2 diabetes, high blood pressure, cardiovascular disease, high cholesterol, and obstructive sleep apnoea. Patients prescribed the drug receive regular check-ups, exercise support, and healthy eating advice.

Approximately 3.4 million people in England could eventually qualify for Mounjaro prescriptions on the NHS. The National Institute for Health and Care Excellence has warned that expanding NHS access could take more than a decade.

Mounjaro affects metabolism and helps regulate energy balance. A head-to-head trial involving 750 obese participants with an average weight of 113 kg, funded by Eli Lilly, found that after 72 weeks Mounjaro produced a 20% weight reduction compared with 14% for Wegovy.

The NHS can prescribe semaglutide, marketed as Wegovy, tirzepatide, and liraglutide, sold as Saxenda, for weight loss. Wegovy is available on the NHS in England, Wales, and Scotland for adults with a BMI of at least 35 and at least one weight-related health condition, or for individuals with cardiovascular disease and overweight BMI below the obesity threshold. NHS Wegovy prescriptions must be accompanied by diet and physical activity programmes and are limited to a maximum of two years.

About 1.6 million people in the UK are using weight-loss drugs, with an estimated 90% paying privately. Both Wegovy and Mounjaro are available for private purchase at supermarkets, pharmacies, and high-street clinics, with injection pens costing between £100 and £300 depending on dosage. Since February 2025, online pharmacies must perform stricter checks to prevent purchase by individuals of healthy weight or with a history of eating disorders, and are required to verify the BMI of patients who complete questionnaires or submit photos.

Common side-effects include nausea, vomiting, bloating, constipation, and diarrhoea. Rare serious side-effects can include gallbladder problems, kidney problems, and depression. Hundreds of reports exist of suspected pancreatic problems among users, but none are confirmed to be caused by the drugs.