Risperidone serotonin antagonism

There is also preliminary data that risperidone, an atypical antipsychotic that antagonizes multiple receptor types including dopamine receptors and serotonin receptors, may affect certain ERP components. A study of chronic risperidone delivery via subcutaneous implants reported increased P20 amplitude but no effects on the N40 component. Risperidone in this study was unable to block the amphetamine-induced decreases in the P20 component, but attenuated amphetamine-induced reduction of the N40 (Siegel et al., 2004). 

Paliperidone, or 9-hydroxyrisperidone, is the major active metabolite of risperidone. It binds to both dopamine Dj and serotonin 5-HT2A receptors, and antagonism at these receptors is thought to account for its therapeutic activity in schizophrenia. It was approved by the US Food and Drug Administration in 2007 for acute and maintenance treatment of schizophrenia it is available in modified-release tablets. The available literature on the pharmacodynamics, pharmacokinetics, clinical efficacy, and tolerability of paliperidone has been extensively reviewed [101 ]. 

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