'Sudden sight loss' risk alert to people taking Wegovy or Mounjaro

'Sudden sight loss' risk alert to people taking Wegovy or Mounjaro A pharmacist has claimed the side effect may lead to 'lasting loss' of vision A very small number of people taking certain medications may face a rare risk of losing their eyesight, experts claim. This side effect can cause no pain, but may end up being permanent and irreversible. Known as Pharmacist Health Raj online (@Therajrpatel), Raj Patel claims that certain injectable medications have a rare chance of being linked to this eye problem. Affecting fewer than one in 10,000 people, health officials are reminding the public of the risks that come from drugs like Ozempic, Wegovy and Mounjaro. He said: "One rare cause [of vision loss] is reduced blood flow to a nerve at the back of your eye. It can cause lasting sight loss even without pain. America's medicines regulator has ordered a warning about a possible increased risk with GLP1 diabetes and weight loss medicines. These include Ozempic, Wegovy and Mounjaro." Studies published in JAMA Ophthalmology found a statistical association between glucagon-like peptide-1 (GLP-1) receptor agonists and NAION, a rare condition that affects the optic nerve and may impair vision. Researchers stress that a direct cause-and-effect link has not been proven, and the evidence is mixed. NAION usually causes sudden, painless vision loss, often noticed after waking. Damage to the optic nerve is often permanent and cannot be reversed. Ozempic is a prescription medication specifically licensed and intended for managing blood sugar levels in adults with type 2 diabetes. While weight loss can occur as a secondary side effect, it is not approved for weight management. The US Food and Drug Administration (FDA) ordered safety-labelling changes for all GLP-1 receptor agonist medications, including semaglutide (Ozempic and Wegovy) and tirzepatide (Mounjaro). The FDA suggests a potential increase in the risk of rare non-arteritic anterior ischemic optic neuropathy (NAION) events and advises patients to immediately report any sudden, painless vision loss or visual disturbances in one eye. Raj Patel claims that those who oversee the drugs in the UK already issue warnings about semaglutide, the medicine inside Ozempic and Wegovy. The UK Medicines and Healthcare products Regulatory Agency (MHRA) updated product information specifically for semaglutide products (Wegovy, Ozempic, and Rybelsus), classifying NAION as a "very rare" side effect affecting up to one in 10,000 people. Ensure our latest health headlines always appear at the top of your Google Search by making us a Preferred Source. Click here to activate or add us as a Preferred Source in your Google search settings These safety warnings began after a 2024 Harvard study of nearly 17,000 patients noticed higher rates of this eye condition in people taking semaglutide compared to other drugs. Regulators later checked 126 clinical trials involving over 134,000 patients and confirmed that rare cases occurred across the entire GLP-1 drug group. Large-scale studies of everyday patient records also indicated a higher relative risk, though the actual chance of developing the condition remains very small, at roughly one extra case per 10,000 people each year. Health officials stress that this research shows a possible link rather than direct proof, especially because health issues like diabetes can cause the eye condition on their own. While US regulators have issued a class-wide warning across all GLP-1 medications, covering both semaglutide (Wegovy) and tirzepatide (Mounjaro), UK guidance is currently more targeted. In the UK, the Medicines and Healthcare products Regulatory Agency (MHRA) has issued a formal safety alert for semaglutide products, while evidence on other drugs in the same class, including Mounjaro, remains under review. As explained in the video, the alert applies only to semaglutide and not Mounjaro (tirzepatide). However, the MHRA advises anyone experiencing sudden vision loss on semaglutide to attend A&E urgently and stop the medicine if NAION is confirmed He said: "Not every vision change is caused by your medicine. But if you get sudden sight loss or quickly worsening eye symptoms or vision problems, you need to go to casualty or A&E. Don't drive, don't stop the treatment yourself and tell the team what you take." Never stop essential medication abruptly without consulting a doctor. If you have any questions or concerns, speak to a GP.