title: Effects of multiple doses of voriconazole on the vision of healthy volunteers: a double-blind, placebo-controlled study.
abstract: OBJECTIVE
  To investigate the effects, and their reversibility, of multiple oral voriconazole doses on a variety of visual tests in healthy male volunteers.
  
  
  METHODS
  Single-center, double-blind, randomized, placebo-controlled, parallel-group study in 36 volunteers who received voriconazole (n=18, 400 mg every 12 h on day 1, then 300 mg every 12 h for 27.5 days) or matched placebo (n=18). Electroretinograms (ERGs) and ophthalmological examinations were performed at screening, throughout the study and at follow-up.
  
  
  RESULTS
  Fifteen (83.3%) volunteers treated with voriconazole experienced ≥1 treatment-related visual adverse events (AEs); these included enhanced visual perceptions, blurred vision, color vision changes and photophobia. No serious AEs were reported. Voriconazole reduced from baseline scotopic maximal a- and b-wave amplitude, shortened implicit time and decreased oscillatory potential amplitude compared with placebo. Under photopic conditions, the 30-Hz flicker response amplitude was significantly reduced and was accompanied by a slight but nonsignificant prolongation of peak time. These effects did not progress in degree over the treatment period, and mean changes from baseline in ERG parameters were similar to placebo by day 43 (14 days after end of treatment). In the first week, color vision discrimination was impaired in the tritan axis, although this resolved by end of treatment and was similar to placebo by day 43. Mean deviation in the static visual field indicated increased sensitivity following voriconazole treatment, correlating with decreased amplitude in conjunction with shortened implicit time.
  
  
  CONCLUSIONS
  Effects of voriconazole on altered visual perception, ERG, color vision and static visual field thresholds are nonprogressive over a treatment period and reversible. It is hypothesized that voriconazole has a pharmacological effect on rod and cone pathways including a possible mechanism of disinhibition that reversibly puts the retina in a more light-adapted state and leads to increased relative contrast sensitivity.
authors.affiliation: Center of Integrative Neuroscience and Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
authors.forename: Eberhart
authors.initials: E
authors.lastname: Zrenner
authors.forename: Konrad
authors.initials: K
authors.lastname: Tomaszewski
authors.forename: Julia
authors.initials: J
authors.lastname: Hamlin
authors.forename: Gary
authors.initials: G
authors.lastname: Layton
authors.forename: Nolan
authors.initials: N
authors.lastname: Wood
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000935:Antifungal Agents / Q000008:administration & dosage* / Q000009:adverse effects; D055253:Color Vision / Q000187:drug effects*; D004311:Double-Blind Method; D004596:Electroretinography / Q000187:drug effects; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D020419:Photoreceptor Cells, Vertebrate / Q000187:drug effects*; D014794:Visual Fields / Q000187:drug effects*; D014796:Visual Perception / Q000187:drug effects*; D065819:Voriconazole / Q000008:administration & dosage* / Q000009:adverse effects; D055815:Young Adult
chemical_list: D000935:Antifungal Agents; D065819:Voriconazole