title: Comparison of the pharmacokinetics and clinical efficacy of new extended-release formulations of methylphenidate.
abstract: BACKGROUND
  Attention-deficit hyperactivity disorder (ADHD) is a common neurobehavioral disorder of which the main features are inattention, hyperactivity and impulsivity. Methylphenidate (MPH) is the mainstay of treatment, but its short duration of action and consequent need for multiple administrations has been problematic for children attending school. Extended-release (ER) formulations have been developed to help overcome the drawbacks associated with immediate-release (IR) preparations.
  
  
  METHODS
  This review focuses on the pharmacokinetics of ER MPH formulations (Concerta®, Equasym XL®/Metadate CD®, Medikinet Retard® and Ritalin LA®). It also attempts to align the properties of each agent with available clinical findings in children/adolescents with ADHD.
  
  
  CONCLUSIONS
  In the author's opinion, Concerta, Equasym XL/Metadate CD, Medikinet Retard and Ritalin LA offer the convenience of once-daily administration with absorption characteristics resembling two or three times daily dosing with IR MPH preparations. All formulations produce plasma concentrations necessary to maintain symptom control during school time in children with ADHD. However, their pharmacokinetic profiles differ with respect to peak plasma levels and the rate at which peak levels are attained and decline. These differences may provide physicians with the opportunity to prescribe a formulation best suited to the symptom profile of individual patients. Additional clinical research is required to clarify further the relative merits of these ER formulations with the goal of enabling a more personalized approach to the management of children with ADHD.
authors.affiliation: Laboratori de Neurofarmacologia, Departament de Ciencies Experimentals i de la Salut, Universitat Pompeu Fabra, PRBB, C/Dr. Aiguader 88, 08003 Barcelona, Spain. rafael.maldonado@upf.edu
authors.forename: Rafael
authors.initials: R
authors.lastname: Maldonado
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy*; D002648:Child; D003692:Delayed-Action Preparations / Q000493:pharmacokinetics; D006801:Humans; D008774:Methylphenidate / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D016032:Randomized Controlled Trials as Topic
chemical_list: D003692:Delayed-Action Preparations; D008774:Methylphenidate