title: Clearance and distribution of ciprofloxacin after intravitreal injection.
abstract: This study was designed to determine the drug concentration and clearance after intravitreal injection of ciprofloxacin. Ciprofloxacin (100 micrograms/0.1 cc) was injected into the vitreous of normal eyes and into eyes that had undergone lensectomy and vitrectomy. Drug concentration was determined using high-pressure liquid chromatography analysis 0.5, 2, 4, and 12 hours after injection. In normal eyes, the elimination half life was 2.2 hours with a distribution volume of 1.2 ml. In aphakic vitrectomized eyes, the half life was 1 hour and the distribution volume was 1.4 ml. The majority of the drug appears to leave via a transretinal route, but clearance was not inhibited by probenecid. Because of the relatively short half life, intravitreal administration of ciprofloxacin for the treatment of endophthalmitis would provide only short-term therapy and would need to be supplemented by other forms of treatment.
authors.affiliation: Department of Ophthalmology, Kentucky Clinic, Lexington 40536.
authors.forename: P A
authors.initials: PA
authors.lastname: Pearson
authors.forename: D P
authors.initials: DP
authors.lastname: Hainsworth
authors.forename: P
authors.initials: P
authors.lastname: Ashton
mesh_terms: D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism*; D002387:Cataract Extraction; D002851:Chromatography, High Pressure Liquid; D002939:Ciprofloxacin / Q000493:pharmacokinetics*; D006207:Half-Life; D007267:Injections; D011817:Rabbits; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism*
chemical_list: D002939:Ciprofloxacin