Asenapine is a new atypical antipsychotic developed for the treatment of schizophrenia and acute mania associated with bipolar disorder. Asenapine shows high affinity (pKi) for numerous receptors, including the serotonin 5-HT1A (8.6), 5-HT1B (8.4), 5-HT2A (10.2), 5-HT2B (9.8), 5-HT2C (10.5), 5-HT5A (8.8), 5-HT6 (9.5), and 5-HT7 (9.9) receptors, the adrenergic α1 (8.9), α2A (8.9), α2B (9.5), and α2C (8.9) receptors, the dopamine D1 (8.9), D2 (8.9), D3 (9.4), and D4 (9.0) receptors, and the histamine H1 (9.0) and H2 (8.2) receptors. Asenapine behaves as an antagonist at all receptors.