A potent antagonist of dopamine receptors (IC50s = 1.0 and 0.9 nM for D2 and D3, respectively);,also avidly binds α1- and α2-adrenergic receptors, histamine H1 receptor, and serotonin (5-HT) receptors 5-HT1D and 5-HT2A (Kis = 10, 80, 3.4, 19, 1.2 nM, respectively).