title: Impact of methylphenidate delivery profiles on driving performance of adolescents with attention-deficit/hyperactivity disorder: a pilot study.
abstract: OBJECTIVE
  Adolescents with attention-deficit/hyperactivity disorder (ADHD) are at high risk for driving accidents. One dose of methylphenidate (MPH) improves simulator driving performances of ADHD-diagnosed adolescents at 1.5 hours post-dose. However, little is known about the effects of different MPH delivery profiles on driving performance throughout the day.
  
  
  METHODS
  This randomized, crossover, single-blind study compared osmotic, controlled-release oral system (OROS) MPH (Concerta) given q.d. to immediate-release MPH (Ritalin) given in equal doses t.i.d. on driving performance among six male ADHD-diagnosed adolescent drivers aged 16 to 19 years. Under each treatment condition, participants were maintained on their medication dosage for 7 days, then drove a sophisticated driving simulator at 2 p.m., 5 p.m., 8 p.m., and 11 p.m. The primary outcome measure was each participant's computer-quantified Impaired Driving Score (IDS).
  
  
  RESULTS
  IDS worsened in the evenings for participants receiving MPH t.i.d. but remained stable when they received once-daily OROS MPH. Participants performed significantly better when receiving OROS MPH q.d. compared with MPH t.i.d. (F = 9.3, df = 1, p =.004). When MPH was given t.i.d., IDS significantly worsened beginning at 8 p.m. compared to OROS MPH (p =.01).
  
  
  CONCLUSIONS
  Participants demonstrated significantly less variability and better driving performance when receiving OROS MPH q.d. compared to MPH t.i.d., particularly in the evenings.
authors.affiliation: Department of Psychiatric Medicine, University of Virginia Health System, Charlottesville, VA 22908, USA. djc4f@virginia.edu
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Cox
authors.forename: R Lawrence
authors.initials: RL
authors.lastname: Merkel
authors.forename: Jennifer Kim
authors.initials: JK
authors.lastname: Penberthy
authors.forename: Boris
authors.initials: B
authors.lastname: Kovatchev
authors.forename: Cheryl S
authors.initials: CS
authors.lastname: Hankin
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D001334:Automobile Driving; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000494:pharmacology; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D006801:Humans; D008297:Male; D008774:Methylphenidate / Q000008:administration & dosage* / Q000494:pharmacology; D010865:Pilot Projects; D016037:Single-Blind Method
chemical_list: D000697:Central Nervous System Stimulants; D003692:Delayed-Action Preparations; D008774:Methylphenidate