A dopamine D1 receptor antagonist (Ki = 5 nM); selective for D1 over D2-4 receptors (Kis = 3,751, >1,000, and 5,934 nM, respectively); binds to D5 receptors (Ki = 4.4 nM); inhibits food intake in a dose-dependent manner in rats (ED50 = 0.84 mg/kg); reduces ethanol intake in Sardinian alcohol-preferring rats and sucrose intake in water-deprived and water-sated rats without affecting food or total fluid intake; suppresses cocaine-induced arrhythmias in anesthetized dogs,