title: Ocular penetration of topical antibiotics: study on the penetration of chloramphenicol, tobramycin and netilmicin into the anterior chamber after topical administration.
abstract: BACKGROUND
  To compare penetration in the aqueous humour of topically applied antibiotics.
  
  
  METHODS
  Randomized prospective study, Department of Ophthalmology, University of Perugia, Italy
  
  
  METHODS
  Patients undergoing cataract surgery.
  
  
  METHODS
  One hundred twenty-two patients were included: 14 received one drop of chloramphenicol suspension; 12 one application of chloramphenicol gel; 11 one drop of netilmicin suspension; 13 one drop of tobramycin suspension; 37 repeated instillations of chloramphenicol suspension every 10 min for a total of four drops; and 35 repeated instillations of chloramphenicol gel every 10 min for a total of four drops. Samples were taken immediately before surgery from the anterior chamber in order to determine the antibiotic by means of high-performance liquid chromatography. Samples were taken 45-190 min after the eye drops were instilled.
  
  
  METHODS
  Intraocular penetration of chloramphenicol, netilmicin and tobramicyn.
  
  
  RESULTS
  After a single administration, netilmicin and tobramycin were undetectable, whereas the chloramphenicol suspension reached a mean concentration of 0.23 ± 0.21 μg/mL, and the chloramphenicol gel a mean concentration of 0.13 ± 0.14 μg/mL. After repeated administrations, the mean concentrations of the chloramphenicol suspension and gel were 0.60 ± 0.26 μg/mL and 0.58 ± 0.18 μg/mL, respectively.
  
  
  CONCLUSIONS
  Tobramycin and netilmicin do not reach detectable concentrations, whereas chloramphenicol, after multiple administrations, reaches concentrations that are effective against Haemophilus influenzae and Haemophilus parainfluenzae, Legionella pneumophila, Moraxella catarrhalis, Neisseria meningitidis, Pasteurella multocida and Streptococcus pneumoniae. This means that chloramphenicol can be rationally used in the prophylaxis and treatment of infections supported by sensitive germs.
authors: Department of Ophthalmology, University of Perugia, Perugia, Italy.
authors: Carlo
authors: C
authors: Cagini
authors: Francesco
authors: F
authors: Piccinelli
authors: Marco
authors: M
authors: Lupidi
authors: Marco
authors: M
authors: Messina
authors: Alessio
authors: A
authors: Cerquaglia
authors: Alessio
authors: A
authors: Cerqualglia
authors: Silvia
authors: S
authors: Manes
authors: Tito
authors: T
authors: Fiore
authors: Roberto M
authors: RM
authors: Pellegrino
mesh_terms: D000287:Administration, Topical; D000867:Anterior Chamber / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001082:Aqueous Humor / Q000378:metabolism; D001419:Bacteria / Q000187:drug effects; D001682:Biological Availability; D002701:Chloramphenicol / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D009428:Netilmicin / Q000493:pharmacokinetics*; D009883:Ophthalmic Solutions; D014018:Tissue Distribution; D014031:Tobramycin / Q000493:pharmacokinetics*
chemical_list: D000900:Anti-Bacterial Agents; D009883:Ophthalmic Solutions; D009428:Netilmicin; D002701:Chloramphenicol; D014031:Tobramycin
keywords: antibiotic; aqueous humour; infectious disease