title: Aqueous humor and plasma concentrations of a compounded 0.2% solution of terbinafine following topical ocular administration to normal equine eyes.
abstract: OBJECTIVE
  To determine the transcorneal penetration and systemic absorption of a compounded 0.2% terbinafine solution following repeated topical administration to normal equine eyes. Sample population  Six healthy adult horses with normal ocular examinations.
  
  
  METHODS
  One eye of each horse received 0.2 mL of a compounded 0.2% terbinafine solution every 4 h for seven doses. During the 1 h following administration of the final dose, multiple peripheral blood samples were obtained, and a single aqueous humor (AH) sample was collected at the end of the hour. AH and plasma concentrations of terbinafine were determined using high pressure liquid chromatography (HPLC). Stability of the formulation was assessed with HPLC analysis over a 14-day time period.
  
  
  RESULTS
  Terbinafine was not detected in the AH or plasma of any horse at any time point. No signs of ocular irritation or systemic toxicity were noted in any horse at any time point. The solution was stable over 14 days.
  
  
  CONCLUSIONS
  Topical ocular administration of compounded 0.2% terbinafine solution does not result in detectable AH or plasma levels following administration to normal equine eyes, suggesting its use for deep corneal or intraocular fungal infections in equine ophthalmology may be limited.
authors.affiliation: Department of Clinical Sciences, North Carolina State University College of Veterinary Medicine, 4700 Hillsborough Street, Raleigh, NC 27606, USA. alison_clode@ncsu.edu
authors.forename: Alison
authors.initials: A
authors.lastname: Clode
authors.forename: Jennifer
authors.initials: J
authors.lastname: Davis
authors.forename: Gigi
authors.initials: G
authors.lastname: Davidson
authors.forename: Jacklyn
authors.initials: J
authors.lastname: Salmon
authors.forename: Heath
authors.initials: H
authors.lastname: Lafevers
authors.forename: Brian
authors.initials: B
authors.lastname: Gilger
mesh_terms: D000042:Absorption; D000818:Animals; D000935:Antifungal Agents / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D001082:Aqueous Humor / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D003315:Cornea / Q000378:metabolism; D005260:Female; D006736:Horses / Q000378:metabolism*; D008297:Male; D009281:Naphthalenes / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D009883:Ophthalmic Solutions; D000077291:Terbinafine
chemical_list: D000935:Antifungal Agents; D009281:Naphthalenes; D009883:Ophthalmic Solutions; D000077291:Terbinafine