Life-threatening side effect warning to anyone using weight-loss jabs | UK | News
Weight loss vaccine users have been warned to be wary of potentially fatal side effects of the increasingly popular method of keeping the pounds off. Product information for GLP-1 drugs marketed by Ozempic, Wegovy, Mounjaro and others has been updated to include a “small risk of serious acute pancreatitis.” The painful condition quickly causes inflammation of the pancreas, a small organ behind the stomach that helps with digestion. Symptoms may include extreme pain in the stomach and back, fever, and vomiting. While some patients begin to feel better within a week, others may develop fatal complications such as sepsis and necrosis, as pancreatic tissue begins to die, leading to organ failure.
The first death officially linked to tirzepatide, or Mounjaro, in the UK, Susan McGowan suffered multi-organ failure, septic shock and pancreatitis following two low-dose injections of the drug in September 2024, with the treatment cited as a “contributing factor” to her passing. Nearly 1.6 million people in England and Wales used weight-loss drugs, including Mounjaro and Wegovy, available on the NHS between early 2024 and 2025, according to research from University College London (UCL).
GLP-1 receptor agonists work by mimicking the hormone GLP-1 to regulate blood sugar and insulin levels and were originally developed to treat type 2 diabetes.
A number of medicines, including Mounjaro, are recommended by the NHS to help people lose weight, while the Medicines and Healthcare products Regulatory Agency (MHRA) has urged patients to see a doctor if they experience symptoms such as severe, persistent stomach pain, nausea and vomiting.
Dr Alison Cave, the MHRA’s chief safety officer, said: “Patient safety is the MHRA’s top priority and we continually monitor the safety and effectiveness of all licensed medicines.”
“For the vast majority of patients prescribed GLP-1, these are safe and effective medications that provide significant health benefits,” he added.
“The risk of these serious side effects is very small, but it is important that patients and healthcare professionals are aware of and alert to the associated symptoms.
“If you or someone you care for is using GLP-1 and you notice symptoms such as severe, persistent stomach pain radiating to your back, which may be accompanied by nausea and vomiting, then we encourage you to speak to a healthcare professional and report the condition through our Yellow Card Programme.”
