Carbamazepine increases phenytoin serum concentration and reduces phenytoin clearance.
Addition of carbamazepine to phenytoin monotherapy resulted in the following significant (p less than 0.05) changes: (1) increased mean phenytoin serum concentration; (2) decreased phenytoin clearance, due to decreased production of phenytoin dihydrodiol and p-hydroxyphenyl-phenylhydantoin; (3) increased phenytoin elimination half-life; and (4) increased drug-related toxicity. Close monitoring is required after addition of carbamazepine to phenytoin.
Browne
T R
TR
Department of Neurology, Boston University School of Medicine, MA.
Szabo
G K
GK
Evans
J E
JE
Evans
B A
BA
Greenblatt
D J
DJ
Mikati
M A
MA
D000328:Adult; D002220:Carbamazepine / Q000494:pharmacology* / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D004827:Epilepsy / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010672:Phenytoin / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D013997:Time Factors
D002220:Carbamazepine; D010672:Phenytoin