| base = Carbamazepinecarbamazepine| add = Olanzapinerisperidone

* Carbamazepine is principally metabolized by CYP3A4 (also CYP2C8), but is also a potent inducer of CYP1A2, CYP3A4 and UDP-glucuronosyltransferases.* Olanzapine is principally metabolized by CYP1A2 and CYP2D6.

* Add olanzapine according to Coadministration with carbamazepine may decrease the general dosing advice plasma concentrations of risperidone and increase dose based on clinical effect or serum concentrationits pharmacologically active metabolite, 9-hydroxyrisperidone. <ref name=”medicatiebewaking”> Schalekamp T. et al, Interacties met Psychofarmaca, Stichting Health Base, Houten, 2002* Risperidone should be given at higher dosage to control psychotic symptoms. </ref> <ref name=”bazire”"drugscom"> Bazire S, Pshychotropic Drug Directory 2007, HealthComm UK Limited, Aberdeen, 2007. {{Drugscominteract|risperidone-with-carbamazepine|risperidone|carbamazepine}}</ref>

* Carbamazepine can reduce olanzapine serum concentration, possible below therapeutic rangePharmacologic response and plasma risperidone levels should be monitored more closely whenever carbamazepine is added to or withdrawn from therapy. <refname="aricarb"> {{Pubmed|986015219934718|Lucas RA Strack DK et al. A pharmacokinetic interaction between Antipsychotic prescribing practices following withdrawal of concomitant carbamazepine and olanzapine: observations on possible mechanism. Eur J Clin Pharmacol 1998Psychiatr Pract. 2009 Nov;5415(6):639442-438}}</ref>