Fluphenazine-d8 (dihydrochloride) is the deuterium labeled Fluphenazine dihydrochloride. Fluphenazine dihydrochloride is a phenothiazine-class D1DR and D2DR inhibitor; used to deliver Fluphenazine to biological systems in studies probing the effects and metabolic fates of this commonly used dopamine antagonist.