Adding valproic acid to risperidone.
- Risperidone is principally metabolized by CYP2D6 to an active metabolite 9-OH-risperidone (paliperidone).
- Valproic acid is principally metabolized by CYP2C9, CYP2C19, CYP2A6 and UDP-glucuronosyltransferases. Valproic acid is an inhibitor of the enzymes CYP2C9, epoxide-hydroxylase and UDP-glucuronosyltransferases.
- Coadministration with risperidone may alter the serum concentrations of valproic acid, although data are conflicting.
- Start valproic acid according to the general dosing advice.
- Dose-related generalised oedema is reported. 
- Antipsychotics lower the seizure threshold and may antagonise the anticonvulsant effect of valproate. 
- ↑ Sanders and Lehrer, Edema associated with addition of risperidone to valproate treatment. J Clin Psychiatry. 1998 Dec;59(12):689-90.
- ↑ Bazire S, Psychotropic Drug Directory 2007, HealthComm UK Limited, Aberdeen, 2007.
The editors of psychiatrienet.nl take the greatest care to provide up-to-date and accurate information on this site. Nevertheless, mistakes and omissions cannot be entirely excluded. No rights devolve from the information provided. The editors and other providers of information to this site accept no responsibility for the content of this site or for the information provided therein; neither do they accept responsibility for possible damages which may derive from the use of the information on this site or from the linked sites. The editorial board accepts no responsibility for the content of the (linked) sites, for access to them, or for the products and services on these sites, nor for the occurrence of errors, viruses, and/or disruptions in service.