Lilly Triples Cost of 'King Kong' Weight Loss Jab Mounjaro

In a move that is sure to anger patients, pharmaceutical company Lilly has announced plans to dramatically increase the UK list price of its popular weight loss injection Mounjaro starting September 1st, 2025. The price of the highest 15mg dose will nearly triple, rising from £122 to £330 per KwikPen, meaning the annual cost will surge from £1,586 to a staggering £4,290.

Lilly claims the price hike is necessary to "address pricing inconsistencies compared to other developed countries" and to align with "new clinical evidence supporting the value of Mounjaro." However, the decision comes at a time when GLP-1 weight loss drugs like Mounjaro are facing global shortages due to surging demand, particularly after high-profile celebrity endorsements.

The company insists it has reached an agreement with the NHS to ensure continued patient access, but the price increase will significantly impact private healthcare providers and their customers. Lilly says it is working with these providers to "maintain patient access," though the final prices charged may include additional processing and consultation fees.

Mounjaro, which contains the active ingredient tirzepatide, has been shown to help patients lose up to 20% of their body weight over 72 weeks through its ability to suppress appetite and make users feel fuller for longer. With two in three UK adults now overweight or obese, and over 5 million living with type-2 diabetes, the demand for such weight loss treatments is only expected to grow in the coming years.