United States | News & Politics

NAION is caused by a loss of blood flow to the optic nerve, which then results in sudden and often permanent vision loss. Not much is known about why it happens, though some likely risk factors include age, high blood pressure, and sleep apnea.

Ophthalmologists at Harvard Medical School and Mass Eye and Ear were the first scientists to publicly highlight the potential connection between NAION and GLP-1s. In July, they published a study showing that people taking semaglutide (the active ingredient in Ozempic and Wegovy) for their diabetes or obesity were more likely to develop NAION than similar patients taking other drugs over a three year period.