Clinical Medicine Insights: Therapeutics

Attention deficit hyperactivity disorder (ADHD) is a common condition and important for the affected individual, their family and society. It manifests with pervasive symptoms of hyperactivity, impulsivity and inattention. In many children with ADHD these symptoms persist into adolescence and adulthood. Drug treatment with psychostimulants, including methylphenidate, is an important part of a comprehensive treatment plan for children with severe ADHD that includes psychosocial, behavioural and educational advice and interventions. Methylphenidate is a central nervous system stimulant, whose mechanism of action is thought to be due to an increase in catecholamines in areas of the brain concerned with motivation and reward. Methylphendiate is available in short acting (immediate release) and longer acting (modified release) forms. Pharmacotherapy for ADHD is in three stages: initiation, maintenance and termination. The efficacy of methylphenidate in terms of reducing core symptoms is 70% as compared to placebo. This efficacy is maintained for at least 24 months. Methylphenidate generally has a favourable side effect profile. The most significant side effects include appetite suppression with an initial deceleration in height velocity, cardiovascular side effects that are not clinically significant in children with no adverse cardiac history, and tics. Methylphenidate is generally well tolerated and liked by children and adolescents with ADHD, who appreciate the benefits that medication has on their behaviour.