Taking Ozempic could cause sudden blindness in one eye, health officials have warned.
The UK’s Medicines and Healthcare products Regulatory Agency (MHRA) said that people taking weight-loss injections risked developing non-arteritic anterior ischemic optic neuropathy (NAION).
NAION occurs due to reduced blood flow to the front part of the optic nerve which typically causes sudden, painless vision loss in one eye. Patients who have had the condition describe it as a blurring or cloudiness of vision.
The warning has been applied to semaglutide, which is sold under the brand name Ozempic for diabetes, and Wegovy for weight loss.
• Weight-loss jab users ‘pile pounds on much faster when they stop’
The MHRA said it had received three reports of NAION in patients taking semaglutide. It stressed that the risk was low, given that an estimated 10.2 million packs of semaglutide have been given to patients in the last five years.
Alison Cave, the MHRA’s chief safety officer, said: “Patient safety is the MHRA’s top priority and we continually monitor the safety and efficacy of all licensed medicines. While the potential risk of NAION for patients prescribed semaglutide is extremely small, it is important that patients and healthcare professionals are alert to the associated symptoms.
“If you, or someone you care for, is taking semaglutide and you notice sudden loss of vision in one eye, then we advise you to urgently attend eye casualty (if available in your area) or A&E and report it via our yellow card scheme [a portal for reporting suspected side-effects].”
The MHRA pointed out that studies showed NAION was “very rarely associated” with semaglutide, meaning it could affect up to one in 10,000 people taking the medication.
In total, about two million people in the UK are estimated to be taking weight-loss injections. Many patients who were taking Mounjaro, also known as tirzepatide, may have switched to Wegovy after a price hike for the drug last September.
• Welcome to Ozempic Town, USA
Last week the MHRA also warned that weight-loss drugs could cause a potentially deadly pancreas illness. It said that acute pancreatitis was a known but infrequent side effect of these drugs, which are taken by two million people in the UK. It causes the pancreas, a small organ behind the stomach that aids digestion, to become acutely inflamed, leading to sudden, severe abdominal pain.
The MHRA said it had received 1,296 safety reports of pancreatitis associated with the use of the jabs in recent years. Other, more common side effects include nausea and vomiting.