The UK medicines regulator has issued a new safety warning for semaglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist.[1] Semaglutide is used to treat type 2 diabetes under the names Ozempic and Rybelsus and for weight loss as Wegovy.[1][7] Varnie refers to anterior ischemic optic neuropathy (NAION).[1] NAION is caused by reduced blood flow to the front of the optic nerve and causes sudden, painless vision loss in one eye.[1] Symptoms include blurred or cloudy vision.[1] Any patient taking semaglutide who experiences a sudden worsening of vision in one or both eyes should see an ophthalmologist immediately.[1]