title: Sildenafil-associated nonarteritic anterior ischemic optic neuropathy.
abstract: OBJECTIVE
  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).
  
  
  METHODS
  Retrospective observational case series.
  
  
  METHODS
  Five patients with NAION who reported the use of sildenafil citrate before the onset of ocular symptoms.
  
  
  METHODS
  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.
authors.affiliation: Department of Ophthalmology, University of Minnesota Medical School, MMC 493, 420 Delaware Street SE, Minneapolis, MN 55455-0501, USA.
authors.forename: Howard D
authors.initials: HD
authors.lastname: Pomeranz
authors.forename: Kyle H
authors.initials: KH
authors.lastname: Smith
authors.forename: William M
authors.initials: WM
authors.lastname: Hart
authors.forename: Robert A
authors.initials: RA
authors.lastname: Egan
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000037:antagonists & inhibitors*; D000328:Adult; D000368:Aged; D007172:Erectile Dysfunction / Q000188:drug therapy; D013700:Giant Cell Arteritis / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D018917:Optic Neuropathy, Ischemic / Q000139:chemically induced* / Q000473:pathology; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects*; D010879:Piperazines / Q000009:adverse effects*; D011687:Purines; D012307:Risk Factors; D000068677:Sildenafil Citrate; D013450:Sulfones
chemical_list: D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate; D015106:3',5'-Cyclic-GMP Phosphodiesterases