A review of the pathophysiology, etiology, and treatment of attention-deficit hyperactivity disorder (ADHD)

Abstract

Objective: To review the pathophysiology, etiology, and treatment of attention-deficit hyperactivity disorder (ADHD).

Data sources and data extraction: A literature search was conducted in PubMed and EMBASE using the terms attention deficit hyperactive disorder, ADHD, pathophysiology, etiology, and neurobiology. Limits applied were the following: published in the past 10 years (January 2003 to August 2013), humans, review, meta-analysis, and English language. These yielded 63 articles in PubMed and 74 in EMBASE. After removing duplicate/irrelevant articles, 86 articles and their relevant reference citations were reviewed.

Data synthesis: ADHD is a neurological disorder that affects children, but symptoms may persist into adulthood. Individuals suffering from this disorder exhibit hyperactivity, inattention, impulsivity, and problems in social interaction and academic performance. Medications used to treat ADHD such as methylphenidate, amphetamine, and atomoxetine indicate a dopamine/norepinephrine deficit as the neurochemical basis of ADHD, but the etiology is more complex. Moreover, these agents have poor adverse effect profiles and a multitude of drug interactions. Because these drugs are also dispensed to adults who may have concomitant conditions or medications, a pharmacist needs to be aware of these adverse events and drug interactions. This review, therefore, focuses on the pathophysiology, etiology, and treatment of ADHD and details the adverse effects and drug interaction profiles of the drugs used to treat it.

Conclusions: Published research shows the benefit of drug therapy for ADHD in children, but given the poor adverse effect and drug interaction profiles, these must be dispensed with caution.

Keywords: ADHD; amphetamine; atomoxetine; attention-deficit hyperactivity disorder; bupropion; clonidine; dopamine; etiology; guanfacine; methylphenidate; norepinephrine; pathophysiology; prefrontal cortex; treatment; treatment guidelines; tricyclic antidepressants.