Too much of a good thing.

Survey of ophthalmology2026PMID: 41520798

View on PubMed DOI: 10.1016/j.survophthal.2026.01.001

Plain Language Summary

Case report of a 38-year-old man on semaglutide presenting with acute painless vision loss, ultimately diagnosed with bilateral sequential NAION (optic disc edema in one eye, pallor in the other) mimicking Foster Kennedy syndrome—a pattern that triggered expensive neuroimaging before GLP-1 RA-associated NAION was recognized. Highlights diagnostic pitfalls when semaglutide-associated NAION presents with atypical bilateral features suggesting intracranial pathology. Contributes a clinically instructive NAION case to the pharmacovigilance literature—cautioning against overlooking semaglutide as the cause when bilateral optic neuropathy presentations prompt extensive neuroradiological evaluation.

Abstract

A 38-year-old man with poorly controlled type 2 diabetes mellitus and arterial hypertension on semaglutide presented with acute, painless, vision loss in the left eye. Ophthalmic examination revealed optic disc edema (ODE) in the left eye and optic disc pallor (ODP) in the right eye, accompanied by severe nonproliferative diabetic retinopathy and cystoid macular edema in both eyes. The combination of ODE in one eye and ODP in the fellow eye raised concern for the Foster Kennedy syndrome secondary to an intracranial mass; however, neuroimaging and systemic evaluation were unremarkable. Ultimately, it was decided the ODP was due to a prior unrecognized non-arteritic anterior ischemic optic neuropathy (NAION) event, and the ODE was the result of an acute NAION in the symptomatic fellow eye (i.e. pseudo-Foster Kennedy syndrome).

Authors

Varghese, Danny; Abdelsalam, Dina; Ibrahim, Safa; Lee, Andrew G; Bhatti, M Tariq

Keywords

Autoregulatory failureBilateral sequentialGlucagon-like peptide-1 receptor agonistNon-arteritic anterior ischemic optic neuropathyOptic disc edemaPseudo–Foster Kennedy syndromeSemaglutide