Attention-deficit/hyperactivity disorder: etiology and pharmacotherapy

Attention-deficit/hyperactivity disorder is a common neurobehavioral disorder of childhood and adolescence. The etiology of attention-deficit/hyperactivity disorder is not well understood. Neurochemical studies suggest, alterations in catecholaminergic, mainly dopaminergic and noradrenergic, transmitter functions markedly contribute to the symptoms of this disorder. The symptoms of attention-deficit/hyperactivity disorder are significantly ameliorated by the agents that specifically influence these neurotransmitters. Animal studies implicate areas of the brain in which these neurotransmitters are most dominant. Psychostimulant medications are generally the first choice in the treatment of attention-deficit/hyperactivity disorder. Approximately 70% of the children treated show improvement in the primary attention-deficit/hyperactivity disorder symptoms and in comorbidity such as conduct disorder, although the benefits may not hold beyond two years. Despite the well-established efficacy and safety of stimulants for attention-deficit/hyperactivity disorder, alternative medicines are still needed for several reasons. About 30% of children and adolescents with this disorder may not respond to stimulants or may be unable to tolerate potential adverse events such as decreased appetite, mood lability and sleep disturbances. Although stimulants do not increase the risk for later substance abuse in attention-deficit/hyperactivity disorder, concerns have been raised about special prescription rules and a potential for abuse by persons other than the attention-deficit/hyperactivity disorder subjects. This review focuses on etiology, assessment, and treatment of attention-deficit/hyperactivity disorder.