Health officials have issued a warning to users of weight loss and diabetes jabs containing semaglutide, including Wegovy, Ozempic and Rybelsus, to be alert for sudden vision problems. The Medicines and Healthcare products Regulatory Agency (MHRA) advises that anyone experiencing sudden loss or rapid worsening of eyesight should seek urgent medical attention.
The warning relates to a rare eye condition called non-arteritic anterior ischemic optic neuropathy (NAION), which affects the optic nerve and can lead to permanent sight loss. According to Manchester Royal Eye Hospital, NAION is sometimes described as a 'small stroke' of the optic nerve and is one of the most common causes of sudden optic nerve-related vision loss in people over 50.
Studies have found that adults with type 2 diabetes taking semaglutide have around twice the risk of developing NAION compared with those not taking the drug. However, the MHRA classifies the side effect as 'very rare', affecting up to one in 10,000 people. Symptoms typically develop suddenly and without pain, often presenting as blurred, cloudy or missing areas in one eye.
The MHRA emphasises that patients should not stop taking prescribed medication without consulting a healthcare professional, as the benefits of semaglutide continue to outweigh the known risks when used as authorised. Anyone experiencing sudden vision loss, blurred vision or rapidly worsening eyesight is advised to seek urgent medical assessment.
