Blonanserin (AD-5423) is an atypical antipsychotic approved in Japan in January, 2008. Relative to many other antipsychotics, blonanserin has an improved tolerability profile, lacking side effects such as extrapyramidal symptoms, excessive sedation, or hypotension.

α1-adrenoceptor:26.7 nM (Ki, rat), D3 receptor:0.494 nM (Ki), D4 Receptor:150 nM (Ki), 5-HT6 receptor:11.7 nM (Ki), α2-adrenoceptor:530 nM (Ki, rat), 5-HT2C receptor:26.4 nM (Ki), 5-HT2A receptor:0.812 nM (Ki), D2 receptor:14.8 nM(Ki), 5-HT2:3.98 nM(Ki), D1 receptor:1070 nM (Ki)

In tests of atypical antipsychotics (risperidone, olanzapine, and aripiprazole), Blonanserin showed the most potent binding affinity for human D3 receptors.Blonanserin transiently increased neuronal firing in the nucleus of the pallidum and ventral tegmental area, but not in the nucleus medius dorsalis or the medial dorsal nucleus of the thalamus, whereas risperidone increased firing in the nucleus ventral tegmental area and in the nucleus medius dorsalis but not in the nucleus dorsalis. in the medial dorsal nucleus of the rat thalamus. Blonanserin consistently increased additional extracellular levels of norepinephrine and dopamine but not serotonin, GABA, or glutamate, whereas risperidone consistently increased levels of norepinephrine, dopamine, and serotonin but not GABA or glutamate.Blonanserin increased the efflux of cortical DA and its metabolites, homovanillic acid and 3,4-dihydroxy Phenylacetic acid.

In tests of atypical antipsychotics (risperidone, olanzapine, and aripiprazole), Blonanserin showed the most potent binding affinity for human D3 receptors.Blonanserin transiently increased neuronal firing in the nucleus of the pallidum and ventral tegmental area, but not in the nucleus medius dorsalis or the medial dorsal nucleus of the thalamus, whereas risperidone increased firing in the nucleus ventral tegmental area and in the nucleus medius dorsalis but not in the nucleus dorsalis. in the medial dorsal nucleus of the rat thalamus. Blonanserin consistently increased additional extracellular levels of norepinephrine and dopamine but not serotonin, GABA, or glutamate, whereas risperidone consistently increased levels of norepinephrine, dopamine, and serotonin but not GABA or glutamate.Blonanserin increased the efflux of cortical DA and its metabolites, homovanillic acid and 3,4-dihydroxy Phenylacetic acid.