UK regulators have issued a warning that users of popular weight loss and diabetes injections containing semaglutide may face a rare but serious risk of sudden vision loss due to an optic nerve condition.

The UK's MHRA has warned users of semaglutide-based medications including Wegovy, Ozempic, and Rybelsus to seek urgent medical attention if they experience sudden vision problems, following evidence that the drug is linked to a doubling of the risk of NAION — a rare eye condition affecting the optic nerve that can cause permanent sight loss, estimated to affect up to 1 in 10,000 users.