Guanfacine Description. Guanfacine hydrochloride is a centrally acting antihypertensive with Î±2-adrenoceptor agonist properties in tablet form for oral administration. The chemical name of Guanfacine hydrochloride is N-Amidino-2-(2,6-dichlorophenyl) acetamide monohydrochloride and its molecular weight is 282.55.