title: Severe QT interval prolongation associated with moxifloxacin: a case report.
abstract: BACKGROUND
  The QT interval prolongation is an adverse effect associated with moxifloxacin. This adverse effect can lead to potentially life-threatening arrhythmias such as Torsades de pointes. We describe a case of severe QT interval prolongation associated with moxifloxacin which may cause the development of Torsades de pointes. There have been no reported case of severe corrected QT interval prolongation caused by moxifloxacin in the patient of normal heart rate.
  
  
  METHODS
  In an 85-year-old Japanese woman, oral moxifloxacin 400 mg daily was initiated for the forearm cellulitis. On the sixth day of oral moxifloxacin administration, monitor electrocardiogram showed prolongation of the corrected QT interval to 523 ms at a rate of 40 beats/min. Electrocardiogram before moxifloxacin therapy showed the corrected QT interval to 460 ms at a rate of 72 beats/min. On the sixth day after moxifloxacin discontinuance, monitor electrocardiogram showed the corrected QT interval to 432 ms at a rate of 70 beats/min.
  
  
  CONCLUSIONS
  This case suggests that electrocardiogram monitoring during moxifloxacin therapy may be necessary in the patients even if they do not have high risk factors for QT interval prolongation.
authors.affiliation: Department of Pharmacy, Kuwana Municipal Hospital, 430 Kitabessyo, Kuwana 511-0819, Japan. stkoide@m2.cty-net.ne.jp.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Koide
authors.forename: Masato
authors.initials: M
authors.lastname: Shiba
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Tanaka
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Muramatsu
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ishida
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kondo
authors.forename: Keiko
authors.initials: K
authors.lastname: Watanabe