Psychostimulants

Stimulants have been in use for the treatment of child and adolescent psychiatric disorders since the 1930's. Various formulations of methylphenidate (MPH) and amphetamine (AMP) have been the subject of hundreds of clinical trials since the late 1960's; controlled trials in patients with attention-deficit/hyperactivity disorders (ADHD) show a response rate of approximately 60% for any given class of stimulant, with a response rate up to 90% if both MPH and AMP are tried. Stimulants act as agonist of both dopamine and norepinephrine, and animal studies suggest action through norepinephrine and dopamine receptors in the prefrontal cortex. Neuroimaging studies have shown that MPH can increase dopamine in brain in vivo and these changes correlate with clinical response. Clinical guidelines as for the use of stimulants are discussed in detail, including recent studies regarding their effects on long-term growth and the cardiovascular system.