A dopamine receptor antagonist (Kis = 9.8 and 1.5 nM for D1 and D2 receptors, respectively); binds to 5-HT2 and 5-HT6, α1-adrenergic, and histamine receptors (Kis = 7.6, 3, 33, and 169 nM, respectively); inhibits dopamine-induced accumulation of cAMP in rat striatal homogenates (IC50 = 330 nM; Ki = 16 nM); decreases stereotypic behavior induced by methylphenidate in mice (ED50 = 0.8 μmol/kg); decreases stereotypic behavior induced by apomorphine in rats and dogs (ED50s = 6.0 and 1.3 μmol/kg, respectively); enhances memory retrieval in rats in an inhibitory avoidance task at 0.7 and 1.4 mg/kg, i.p.