UK reports 150,000 adverse reactions and over 100 deaths linked to weight‑loss drugs

Analysis of data from the UK Medicines and Healthcare products Regulatory Agency (MHRA) shows roughly 150,000 reports of adverse reactions to the weight‑loss medicines Mounjaro (tirzepatide), Wegovy (semaglutide) and Saxenda (liraglutide). The Yellow Card system recorded 100,810 reports for Mounjaro, including 10,434 serious cases and 98 deaths; 44,073 reports for Wegovy with 4,892 serious cases and 37 deaths; and 3,021 reports for Saxenda with 734 serious cases and 18 deaths. Most reactions were gastrointestinal, and the agency warned that the reported deaths are not necessarily caused by the drugs, noting many patients have other serious conditions.

In January, the MHRA updated safety warnings for these drugs after a rise in acute pancreatitis cases, 1,143 reported overall, 17 of which were fatal. Meanwhile, in the United States, about 4,400 lawsuits have been filed against manufacturers Novo Nordisk and Eli Lilly alleging severe health complications from the same medications. MHRA safety chief Dr. Alison Keay emphasized that the drugs remain safe and effective for the vast majority of patients when used under medical supervision, but urged immediate medical attention for severe abdominal pain, vomiting, or persistent nausea.