Non-arteritic anterior ischemic optic neuropathy, a rare condition involving sudden, usually painless vision loss in one eye from reduced blood flow to the optic nerve. European regulators have listed it as a very rare possible side effect of semaglutide (on the order of 1 in 10,000), and as of mid-2026 the U.S. FDA had not added it to the label. Regardless of suspected cause, sudden vision change is an emergency. Seek care immediately.
Related terms: Semaglutide · Pancreatitis