title: Non-arteritic anterior ischaemic optic neuropathy and the treatment of erectile dysfunction.
abstract: OBJECTIVE
  To determine the association between Viagra (sildenafil) and Cialis (tadalafil) and non-arteritic anterior ischaemic optic neuropathy (NAION).
  
  
  METHODS
  A retrospective matched case-control study was conducted. 38 cases of NAION in males were identified from an academic ophthalmology practice in Birmingham, Alabama, and matched (on age) to 38 controls without a history of NAION. Self reported information regarding past and current use of Viagra and/or Cialis was obtained via a telephone questionnaire from interviewers who were not blind to case status.
  
  
  RESULTS
  Overall, males with NAION were no more likely to report a history of Viagra or Cialis use compared to similarly aged controls (odd ratio (OR) 1.75, 95% confidence interval (CI) 0.48 to 6.30 and OR 1.82, 95% CI 0.21 to 15.39). However, for those with a history of myocardial infarction, a statistically significant association was observed (OR 10.7, 95% CI 1.3 to 95.8). A similar association was observed for those with a history of hypertension though it lacked statistical significance (OR 6.9, 95% CI 0.8 to 63.6).
  
  
  CONCLUSIONS
  For men with a history of myocardial infarction or hypertension the use of Viagra or Cialis may increase the risk of NAION. Physicians prescribing these medications to patients with these conditions should warn them about the potential risk of NAION.
authors.affiliation: Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, 700 S 18th Street, Suite 609, Birmingham, AL 35294-0009, USA. mcgwin@uab.edu
authors.forename: G
authors.initials: G
authors.lastname: McGwin
authors.forename: M S
authors.initials: MS
authors.lastname: Vaphiades
authors.forename: T A
authors.initials: TA
authors.lastname: Hall
authors.forename: C
authors.initials: C
authors.lastname: Owsley
mesh_terms: D002243:Carbolines / Q000009:adverse effects*; D016022:Case-Control Studies; D007172:Erectile Dysfunction / Q000188:drug therapy; D006801:Humans; D006973:Hypertension / Q000150:complications; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications; D016017:Odds Ratio; D018917:Optic Neuropathy, Ischemic / Q000139:chemically induced*; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects*; D010879:Piperazines / Q000009:adverse effects*; D011687:Purines; D012189:Retrospective Studies; D000068677:Sildenafil Citrate; D013450:Sulfones; D000068581:Tadalafil; D014665:Vasodilator Agents / Q000009:adverse effects*
chemical_list: D002243:Carbolines; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068581:Tadalafil; D000068677:Sildenafil Citrate