Nonarteritic anterior ischemic optic neuropathy after rapid weight loss during semaglutide therapy: a case report

Semaglutide, a glucagon-like peptide-1 receptor agonist, is increasingly used for obesity management; however, concerns have recently emerged regarding potential ocular adverse events, including nonarteritic anterior ischemic optic neuropathy (NAION). Herein, we report a case of NAION that developed after marked, rapid weight loss during semaglutide therapy in a young man with multiple vascular risk factors. A 42-year-old man presented with acute visual disturbance in the right eye after losing approximately 40 kg over 2 months while receiving semaglutide (Wegovy) for obesity treatment. The patient's medical history included diabetes mellitus, hypertension, dyslipidemia, and a history of smoking. Ophthalmic examination revealed right optic disc edema and a corresponding inferior visual field defect. Magnetic resonance imaging and laboratory investigations revealed no other definite causes of optic neuropathy. He was diagnosed with NAION, which was temporally associated with semaglutide therapy and rapid weight reduction. Semaglutide was discontinued, and high-dose intravenous methylprednisolone was administered. At 6 months, the optic disc edema had resolved, leaving mild disc pallor, though the visual field defect persisted. Although causality cannot be established from a single case, this report highlights the need for clinical vigilance regarding optic neuropathy in patients receiving semaglutide, particularly in the setting of rapid weight loss.