AIM: To give some information for rational administration of oral antiepileptic drugs to epileptic patients in clinic METHODS: The serum concentrations of oral phenytoin sodium, phenobarbital and carbamazepine were determined in 88,63 and 63 epileptic patients( total 214 times) by fluorescence polarization immunoassay, respectively The individualized drugs administration schemes were provided RESULTS: The sensitivity to the three kinds of antiepileptic drugs varied in different patients CONCLUSIONS: The administration of oral antiepileptic drugs to epileptic patients must be based on the data of drug concentration in serum We must comprehensively consider the other factors