Sildenafil-associated nonarteritic anterior ischemic optic neuropathy.

PURPOSE: To describe the clinical features of five patients who developed nonarteritic anterior ischemic optic neuropathy (NAION) after ingestion of sildenafil citrate (Viagra; Pfizer Pharmaceuticals, New York, NY).

DESIGN: Retrospective observational case series.

PARTICIPANTS: Five patients with NAION who reported the use of sildenafil citrate before the onset of ocular symptoms.

MAIN OUTCOME MEASURES: The symptoms presented, history, ophthalmic examination, and visual field examination of each patient.

RESULTS: Nonarteritic anterior ischemic optic neuropathy developed in one eye within minutes to hours after ingestion of sildenafil. Four of the five patients had no vascular risk factors for ischemic optic neuropathy. The patients all developed unilateral blurry vision, altitudinal visual field defects, and optic disc edema. Each of the patients was noted to have a small cup-to-disc ratio in the unaffected optic nerve.

CONCLUSIONS: Sildenafil citrate may be associated with NAION. A small cup-to-disc ratio may be a risk factor for development of NAION in association with the use of sildenafil.