Alpha-2 Adrenergic Receptors and Attention-Deficit/Hyperactivity Disorder
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Pharmacologic management of attention-deficit/hyperactivity disorder (ADHD) has expanded beyond stimulant medications to include α-2 adrenergic agonists. These agents exert their actions through presynaptic stimulation and likely involve facilitation of dopamine and noradrenaline neurotransmission, both of which are thought to play critical roles in the pathophysiology of ADHD. Furthermore, frontostriatal dysfunction giving rise to neuropsychological weaknesses has been well-established in patients with ADHD and may explain how α-2 agents exert their beneficial effects. In the following review, we consider relevant neurobiological underpinnings of ADHD with respect to why α-2 agents may be effective in treating this condition. We also review new formulations of α-2 agonists, emerging data on their use in ADHD, and implications for clinical practice. Integrating knowledge of pathophysiologic mechanisms and mechanisms of drug action may inform our medication choices and facilitate treatment of ADHD and related disorders.
KeywordsGuanfacine Clonidine Prefrontal Noradrenaline ADHD
Dr. Kollins has served as a paid consultant for the National Institutes of Health/Center for Scientific Review and has had research funded in part by grants from the National Institutes of Health and the National Institute on Drug Abuse.
Dr. Kollins has served as a consultant for and received grants from Addrenex Pharmaceuticals/Shionogi Pharma Media, Otsuka Pharmaceutical Co., Shire, and Supernus Pharmaceuticals, and was paid to conduct training by United Biosource Corp. No other potential conflicts of interest relevant to this article were reported.
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