The Sound of Evolution
Guanfacine
Mechanism of action:
Guanfacine is a selective α₂A-adrenergic receptor agonist. Guanfacine has high selectivity for the α₂A subtype and acts particularly on postsynaptic α₂A receptors in the prefrontal cortex and the brainstem vasomotor center. After activating α₂A receptors, guanfacine regulates signal transmission within prefrontal cortical networks and reduces excessive neural noise, thereby enhancing the efficiency of neural activity related to executive function. In the brainstem vasomotor center, it suppresses sympathetic neuronal activity and inhibits the release of norepinephrine, thereby reducing sympathetic outflow.
Reference(s):
1. Cruz MP et al. (2010). Guanfacine Extended-Release Tablets (Intuniv), a Nonstimulant Selective Alpha(2A)-Adrenergic Receptor Agonist For Attention-Deficit/Hyperactivity Disorder. P T.
2. Kirch W et al. (1980). Elimination of guanfacine in patients with normal and impaired renal function. Br J Clin Pharmacol.
3. Minns AB et al. (2010). Guanfacine overdose resulting in initial hypertension and subsequent delayed, persistent orthostatic hypotension. Clin Toxicol (Phila).