Paliperidone

Paliperidone is the primary active metabolite of risperidone. The mechanism of action is unknown but it is likely to act via a similar pathway to risperidone. It has been proposed that the drug's therapeutic activity in schizophrenia is mediated through a combination of central dopamine Type 2 (D2) and serotonin Type 2 (5HT2A) receptor antagonism. Paliperidone is also active as an antagonist at alpha 1 and alpha 2 adrenergic receptors and H1 histaminergic receptors, which may explain some of the other effects of the drug. Paliperidone was approved by the FDA for treatment of schizophrenia on December 20, 2006. It is available as an extended-release tablet, a once-monthly intramuscular injection, an every-three-month intramuscular injection, and a twice-yearly gluteal injection.

As an oral extended-release tablet and a once-monthly extended-release suspension for intramuscular injection, paliperidone is indicated for the treatment of adults and adolescents with schizophrenia and in the treatment of schizoaffective disorder in combination with antidepressants or mood stabilizers. Paliperidone is also available in both an every-three-month and twice-yearly extended-release suspension for intramuscular injection for the treatment of schizophrenia.