title: In vitro comparison of the cytotoxic effects of clinically available ophthalmic solutions of fluoroquinolones on human keratocytes.
abstract: OBJECTIVE
  To compare the cytotoxic effects of preserved versus unpreserved commercially available ophthalmic preparations of fluoroquinolones on human keratocytes in vitro.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Human keratocytes in vitro were incubated for 15 or 60 minutes with commercially available preparations containing different types of fluoroquinolones, with or without benzalkonium chloride. We examined the morphologic aspects of the cultures by an inverted-phase contrast microscope and the release of cytoplasmic enzyme lactate dehydrogenase into the medium immediately or 24 hours after exposure to drugs.
  
  
  RESULTS
  Whereas preparations of ofloxacin, norfloxacin, and gatifloxacin, all containing benzalkonium chloride, and moxifloxacin, which is preservative-free, displayed various degrees of cytotoxicity in our model, the unpreserved monodose preparation of norfloxacin was virtually devoid of harmful effects under our experimental conditions.
  
  
  CONCLUSIONS
  Our in vitro results indicated the cytotoxic role of preservatives in commercial preparations of fluoroquinolones and the relative nontoxicity of monodose unpreserved norfloxacin, even when keratocytes were incubated with this formulation for 6 hours.
authors.affiliation: Department of Oto-Neuro-Ophthalmological Surgical Sciences, University of Florence, Florence, Italy.
authors.forename: Rita
authors.initials: R
authors.lastname: Mencucci
authors.forename: Iacopo
authors.initials: I
authors.lastname: Paladini
authors.forename: Domenico E
authors.initials: DE
authors.lastname: Pellegrini-Giampietro
authors.forename: Ugo
authors.initials: U
authors.lastname: Menchini
authors.forename: Tania
authors.initials: T
authors.lastname: Scartabelli
mesh_terms: D000900:Anti-Bacterial Agents / Q000633:toxicity*; D001372:Aza Compounds / Q000633:toxicity; D001548:Benzalkonium Compounds / Q000633:toxicity*; D002478:Cells, Cultured; D060527:Corneal Keratocytes / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D003470:Culture Media; D024841:Fluoroquinolones / Q000633:toxicity*; D000077734:Gatifloxacin; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008858:Microscopy, Phase-Contrast; D000077266:Moxifloxacin; D009643:Norfloxacin / Q000633:toxicity; D015242:Ofloxacin / Q000633:toxicity; D009883:Ophthalmic Solutions / Q000633:toxicity; D011310:Preservatives, Pharmaceutical / Q000633:toxicity*; D011804:Quinolines / Q000633:toxicity
chemical_list: D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D001548:Benzalkonium Compounds; D003470:Culture Media; D024841:Fluoroquinolones; D009883:Ophthalmic Solutions; D011310:Preservatives, Pharmaceutical; D011804:Quinolines; D015242:Ofloxacin; D007770:L-Lactate Dehydrogenase; D000077734:Gatifloxacin; D009643:Norfloxacin; D000077266:Moxifloxacin