title: Vitreous and aqueous penetration of orally and topically administered moxifloxacin.
abstract: OBJECTIVE
  It was the aim of this study to compare the pharmacokinetics of moxifloxacin (MFLX) hydrochloride in rabbits after topical and oral administration.
  
  
  METHODS
  Three 50-μl applications of MFLX (0.5%) topical ophthalmic solution were instilled into the cul-de-sac of New Zealand white rabbits at 15-min intervals. Aqueous and vitreous samples were collected and analyzed 30-240 min after the final instillation. Assays were performed using high-performance liquid chromatography. MFLX (16 mg/kg of body weight) was administered orally. Drug concentrations in aqueous, vitreous and serum samples, collected at 30-360 min after administration, were determined using high-performance liquid chromatography.
  
  
  RESULTS
  After topical administration, the maximum concentrations of MFLX in the aqueous and vitreous samples were 10.2 ± 1.6 μg/ml (30 min; n = 6) and 0.10 ± 0.03 μg/ml (30 min; n = 6), respectively. After oral administration, the maximum concentrations in the aqueous, vitreous and serum samples were 0.9 ± 0.3 μg/ml (120 min; n = 6), 0.7 ± 0.2 μg/ml (240 min; n = 6) and 1.6 ± 0.9 μg/ml (120 min; n = 6), respectively. The percentages of serum MFLX concentration in the aqueous and vitreous samples after oral administration were 55.2 and 41.7%, respectively.
  
  
  CONCLUSIONS
  The aqueous concentration of MFLX was about 10-fold higher after topical than after oral administration. However, intravitreal MFLX concentrations after oral administration were about 7-fold higher than those after topical administration. The MFLX concentrations in the aqueous humor following oral administration exceeded the minimum inhibitory concentration for 90% of the bacteria involved in ocular infection.
authors.affiliation: Department of Ophthalmology, Kanazawa Medical University, Uchinada, Japan. fukuda@kanazawa-med.ac.jp
authors.forename: Masamichi
authors.initials: M
authors.lastname: Fukuda
authors.forename: Naoko
authors.initials: N
authors.lastname: Shibata
authors.forename: Hiromi
authors.initials: H
authors.lastname: Osada
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yamashiro
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sasaki
mesh_terms: D000284:Administration, Oral; D000287:Administration, Topical; D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001082:Aqueous Humor / Q000378:metabolism*; D001372:Aza Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D024841:Fluoroquinolones; D000077266:Moxifloxacin; D009883:Ophthalmic Solutions / Q000008:administration & dosage / Q000493:pharmacokinetics; D011804:Quinolines / Q000008:administration & dosage / Q000493:pharmacokinetics*; D011817:Rabbits; D014822:Vitreous Body / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D009883:Ophthalmic Solutions; D011804:Quinolines; D000077266:Moxifloxacin