title: Effect of amantadine on the sleep-wake cycle of an inpatient with brain injury.
abstract: BACKGROUND
  A previous study suggested that the routine use of drugs intended to improve attention and arousal, such as methylphenidate, tend to have a variable but not significant effect on sleep-wake cycles. As amantadine is a frequently employed drug in brain injury rehabilitation, with known effects on fatigue and motor processing speed, this study examined the effect of amantadine on the sleep-wake behaviour of patients with brain injury undergoing rehabilitation.
  
  
  METHODS
  This was a naturalistic observation using an observationally defined sleep-wake distribution for a total of 43 subjects with brain injury. Identified patients were observed for a full 24 hours a day 2 weeks before and 2 weeks after starting amantadine. Some of these patients (n = 12) had been administered amantadine on clinical grounds and, for this paper, served as the experimental group, while the drug naive (n = 31) served as a control. Three outcome measures were operationalized: hours of sleep in 24 hours, hours of sleep during daytime and hours of sleep during night-time.
  
  
  RESULTS
  The average number of hours of sleep during a 24-hour period was not significantly different for the two cohorts. Similarly hours of sleep during daytime and hours of sleep during night-time were on average the same for the two groups. The data suggest that amantadine has no direct bearing on sleep/wake cycles using these parameters.
  
  
  CONCLUSIONS
  This study fails to demonstrate that the use of amantadine on an inpatient brain injury population will affect sleep/wake quantity.
authors.affiliation: Department of Behavioral Medicine, College of Medicine & Health Sciences, Sultan Qaboos University, PO Box 35, Al-Khoudh 123, Muscat, Sultanate of Oman. adawi@squ.edu.om
authors.forename: Samir
authors.initials: S
authors.lastname: Al-Adawi
authors.forename: Heather
authors.initials: H
authors.lastname: Hoaglin
authors.forename: Fariba
authors.initials: F
authors.lastname: Vesali
authors.forename: Atsu S S
authors.initials: AS
authors.lastname: Dorvlo
authors.forename: David T
authors.initials: DT
authors.lastname: Burke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000547:Amantadine / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D001930:Brain Injuries / Q000188:drug therapy* / Q000503:physiopathology; D015259:Dopamine Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D012189:Retrospective Studies; D020178:Sleep Disorders, Circadian Rhythm / Q000188:drug therapy*; D013997:Time Factors; D055815:Young Adult
chemical_list: D015259:Dopamine Agents; D000547:Amantadine