Felbamate in vitro metabolism by rat liver microsomes
Adusumalli, V.E.; Wong, K.K.; Kucharczyk, N.; Sofia, R.D.
Drug Metabolism and Disposition the Biological Fate of Chemicals 19(6): 1135-1138
1991
ISSN/ISBN: 0090-9556 PMID: 1687021 Document Number: 367800
Incubation of [14C]felbamate at 37.degree. C for 60 min with liver microsomes from untreated Sprague-Dawley rats converted 10% of the drug to the p-hydroxy (6%) and 2-hydroxy (4%) metabolites. With microsomes from phenobarbital-pretreated rats, 21% of the drug was metabolized to the p-hydroxy (7.5%) and 2-hydroxy (13.5%) metabolites. With microsomes from felbamate-pretreated rats, up to 25% of drug was metabolized to the p-hydroxy (5%) and 2-hydroxy (20%) metabolites. In addition, a small amount of the monocarbamate metabolite was also present, but no other metabolites were formed. Coincubations of [14C]phenytoin with felbamate had no effect on the metabolism of phenytoin, whereas the amount of [14C]felbamate metabolized in the presence of phenytoin decreased by 30-38%.