epileptic patients on maintenance phenytoin therapy have mixed saliva phenytoin concentrations similar to 'free ' drug levels measured directly in serum or cerebrospinal fluid ( csf ) , salivary phenytoin levels are approximately 10 % of the total serum level in treated epileptic patients and in normal subjects after ingestion of a single oral dose .
C0031507
phenytoin
C0014544
epileptic