An FDA analysis of 126 clinical trials involving 134,253 participants found higher NAION incidence among GLP-1 drug users than among those taking placebos or other diabetes medications. The US Food and Drug Administration (FDA) has warned of a potential increased risk of a rare eye condition that can cause sudden and permanent vision loss among patients taking glucagon-like peptide-1 receptor agonist (GLP-1 RA) medications, widely used to treat type 2 diabetes and.