People taking the weight-loss injection Wegovy may face a higher risk of a rare condition that can lead to sudden and permanent vision loss, according to new research.
Popular weight loss jab linked to higher risk of vision loss
A study published in the British Journal of Ophthalmology found that patients using the popular slimming jab were nearly five times more likely to develop non-arteritic anterior ischemic optic neuropathy (NAION), sometimes described as an "eye stroke", compared with people taking Ozempic.
Both Wegovy and Ozempic belong to a class of medicines called GLP-1 receptor agonists, which have been widely praised for helping people manage obesity and type 2 diabetes. These drugs mimic a natural hormone that regulates appetite and blood sugar levels, helping users feel fuller for longer and reduce calorie intake.
The study analysed reports submitted to the US Food and Drug Administration's adverse event reporting system between December 2017 and December 2024. Canadian researchers compared cases linked to different forms and doses of semaglutide-based treatments, including Wegovy, Ozempic and Rybelsus, as well as the newer drug tirzepatide (Mounjaro).
The eye condition remains rare, affecting around one in 10,000 people taking semaglutide. However, the researchers found the strongest association with Wegovy, with men appearing to face three times the risk compared with women. No increased risk was found among people taking the oral diabetes medication Rybelsus or Mounjaro.
Dr Alison Cave, chief safety officer at the Medicines and Healthcare products Regulatory Agency, explained that the overall risk is "extremely low".
She said: "The risk of NAION in patients prescribed semaglutide is extremely low.
"However, as with all medicines, patients and prescribers need to be aware of the symptoms of potential side effects, even if the risk is very small, to ensure patients receive the appropriate treatment promptly should they occur."
A spokesperson for Novo Nordisk, which manufactures Wegovy and Ozempic, said patient safety is closely monitored.
The company said: "Patient safety is our top priority, and we take any reports about adverse events from the use of our medicines very seriously.
"We work closely with authorities and regulatory bodies from around the world to continuously monitor the safety profile of our products."