Guanfacine is a selective α2A receptor agonist.Target: α2A ReceptorGuanfacine is a sympatholytic. It is a selective α2A receptor agonist. These receptors are concentrated heavily in the prefrontal cortex and the locus coeruleus, with the potential to improve attention resulting from interaction with receptors in the former. Guanfacine lowers both systolic and diastolic blood pressure by activating the central nervous system α2A norepinephrine autoreceptors, which results in reduced peripheral sympathetic outflow and thus a reduction in peripheral sympathetic tone [1, 2].

References:
[1]. Kolar, D., et al., Treatment of adults with attention-deficit/hyperactivity disorder. Neuropsychiatr Dis Treat, 2008. 4(2): p. 389-403.
[2]. Zwieten, P.v., M. Thoolen, and P. Timmermans, The pharmacology of centrally acting antihypertensive drugs. British journal of clinical pharmacology, 1983. 15(Supplement s4): p. 455S-462S.