Risperidone Oxcarbazepine

First, optimize current mood stabilizer or initiate mood-stabilizing medication lithium,0 valproate,0 or carba-mazepine0 Consider adding a benzodiazepine (lorazepam or clonazepam) for short-term adjunctive treatment of agitation or insomnia if needed Alternative medication treatment options carbam-azepine0 if patient does not respond or tolerate, consider atypical antipsychotic (e.g., olanzapine, quetiapine, risperidone) or oxcarbazepine. 

Another group of mood-stabilizing drugs that are also anticonvulsant agents have become more widely used than lithium. These include carbamazepine and valproic acid for the treatment of acute mania and for prevention of its recurrence. Lamotrigine is approved for prevention of recurrence. Gabapentin, oxcarbazepine, and topiramate are sometimes used to treat bipolar disorder but are not approved by FDA for this indication. Aripiprazole, chlorpromazine, olanzapine, quetiapine, risperidone, and ziprasidone are approved by FDA for the treatment of manic phase of bipolar disorder. Olanzapine plus fluoxetine in combination and quetiapine are approved for the treatment of bipolar depression. 

Lithium and valproate are the mainstays of treatment for both acute mania and prophylaxis for recurrent manic and depressive episodes. Anticonvulsants such as lamotrigine, carbamazepine, and oxcarbazepine and atypical antipsy-chotics such as aripizrazole, olanzapine, risperidone, queti-... 

Muscatello MR, Pacetti M, Cacciola M, et ai. Plasma concentrations of risperidone and olanzapine during coadministration with oxcarbazepine. Epilepsia 2005 46 771-774. 

Carbamazepine increases the metabolism of risperidone, resulting in reduced risperidone levels. Oxcarbazepine dose not significantly affect the pharmacokinetics of risperidone. 

A study in 12 patients taking risperidone 2 to 6 mg daily found that the addition of oxcarbazepine for 5 weeks, at an initial dose of 300 mg daily increased to 900 mg to 1.2 g after one week, had no significant effects on the pharmacokinetics of risperidone. Coneurrent use was generally well tolerated. ... 

Carbamazepine is a known potent enzyme inducer, which appears to increase the metabolism of risperidone by the cytochrome P450 isoenzyme CYP2D6 (although other isoenzymes may play a part). The extent of the interaction appears to be related to CYP2D6 genotype (see Genetic factors , (p.4)). Oxcarbazepine is not known to affect CYP2D6-mediated metabolism. 

No special consideration or monitoring appears necessary with concurrent oxcarbazepine and risperidone treatment. 

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