A new study links GLP-1 drugs such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound) to a small increase in the risk of ischemic optic neuropathy, a rare condition in which reduced blood flow to the optic nerve causes sudden, often permanent loss of part of the vision in one eye. Rutgers researchers who analyzed US adults aged 18 to 65 with Type 2 diabetes found about three to four additional cases per 10,000 patients treated with GLP-1s over 18 months.
Most cases occurred in men and in adults aged 50 to 65. The study shows an association, not proof that the drugs directly cause the damage, and the absolute risk remains very low. Anyone taking these medications who notices sudden blurring, dimming, or missing areas of vision should get prompt eye care. The study was published in Annals of Internal Medicine (2026; DOI 10.7326/ANNALS-25-00860).
Image: Ozempic 0.5 mg semaglutide pen box. Photo by Chemist4U, CC BY-SA 2.0, via Wikimedia Commons.