title: Deposits of topical norfloxacin in the treatment of bacterial keratitis.
abstract: OBJECTIVE
  Fluoroquinolone solutions are widely used in therapy of bacterial keratitis. These drugs are safe, and their ocular side effects are mild and not serious in nature. The most frequent untoward effect associated with ciprofloxacin therapy has been a white crystalline deposit. This deposit has not been reported after using the other commercially available quinolones, ofloxacin and norfloxacin.
  
  
  METHODS
  We present three cases of norfloxacin deposits after treatment of bacterial keratitis.
  
  
  RESULTS
  In the three cases, the norfloxacin was substituted for another antibiotic effective against the bacteria, and the precipitate spontaneously resolved in all cases within a few days with no untoward ocular effect.
  
  
  CONCLUSIONS
  Crystalline corneal deposits can develop during topical norfloxacin therapy. The exact factors contributing to the formation are unknown, although the differences in the tear pH/solubility could be involved. Clinicians should be aware of this ocular side effect.
authors.affiliation: Hospital General de Móstoles, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Castillo
authors.forename: J M
authors.initials: JM
authors.lastname: Benitez del Castillo
authors.forename: N
authors.initials: N
authors.lastname: Toledano
authors.forename: D
authors.initials: D
authors.lastname: Diaz-Valle
authors.forename: O
authors.initials: O
authors.lastname: Sayagues
authors.forename: J
authors.initials: J
authors.lastname: Garcia-Sanchez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000009:adverse effects* / Q000627:therapeutic use; D011232:Chemical Precipitation; D003315:Cornea / Q000187:drug effects* / Q000382:microbiology / Q000473:pathology; D003316:Corneal Diseases / Q000139:chemically induced* / Q000473:pathology; D003460:Crystallization; D015818:Eye Infections, Bacterial / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007634:Keratitis / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D008297:Male; D009643:Norfloxacin / Q000009:adverse effects* / Q000627:therapeutic use; D009883:Ophthalmic Solutions; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D013210:Staphylococcus / Q000302:isolation & purification
chemical_list: D000890:Anti-Infective Agents; D009883:Ophthalmic Solutions; D009643:Norfloxacin