Mounjaro Dominates UK Weight-Loss Market, But Price Hike Looms

As of August 29th, 2025, the weight-loss drug Mounjaro has firmly established itself as the dominant player in the UK market. Just over 20 months after its arrival in the country, Mounjaro now accounts for more than half of the 1.5 million people taking weight-loss medications in the UK.

Dubbed the "King Kong" of weight-loss drugs, Mounjaro has proven to be highly effective, with a trial presented at the European Congress on Obesity this year showing that it helped almost a third of people lose a quarter of their body weight. In comparison, Mounjaro's rival, Wegovy, saw just 16% of users achieve the same results.

However, users of Mounjaro are now facing a significant challenge. The drug's manufacturer, Eli Lilly, has announced that it will be raising the price of Mounjaro by a staggering 170% starting on September 1st. This price hike is expected to lead to a surge in demand, leaving some pharmacists suggesting that people switch to Wegovy instead.

While Wegovy is a viable alternative, it is important for users to consult with their doctors before making the switch. The two drugs have some differences, such as active ingredients, dosage schedules, and manufacturers, which could impact their effectiveness and side effects. Ultimately, the decision to switch should be made in close collaboration with a healthcare professional.