A muscarinic receptor antagonist (Kis = 0.48, 6.3, 3.9, 2.4, and 6.3 nM for M1-5 receptors, respectively); inhibits binding of [3H]QNB to muscarinic receptors in tissue homogenates (IC50s = 79, 52, and 38 nM for rat heart, rat lung, and guinea pig lung, respectively) and in vivo (IC50s = 2.5, 1.1, and 1.2 mg/kg for mouse cerebral cortex, cerebellum, and heart, respectively); increases spontaneous and electrically-evoked DA and electrically-evoked ACh release from preincubated rabbit caudate nucleus slices in vitro when used at a concentration of 1 μM; an uncompetitive NMDA receptor antagonist and inhibits NMDA-evoked ACh release (10 μM); reduces physostigmine-induced tremor in rats in a dose-dependent manner (0.01-1.0 mg/kg)