Compliance monitoring in epileptic patients

Poor patient compliance is one of the major causes of non responsiveness to antiepileptic drug therapy. Compliance is mostly assessed by self reporting, pill counting and plasma drug level estimation. However, none of them is fool proof. Subtherapeutic plasma drug levels can be due to poor compliance or need for higher dosage. Therefore, in the present study, 20 adult non responsive epileptic patients showing subtherapeutic plasma phenytoin levels inspite of receiving standard phenytoin therapy and history of good compliance were admitted in the clinical pharmacology ward and received supervised drug treatment for five days after which plasma phenytoin levels in 14 patients increased to therapeutic range. All except one (i.e. 9 out of 10) patients showing phenytoin levels < 5 ug/ml inspite of phenytoin dosage of > 300 mg/d and history of good compliance were found to be noncompliant. Hence adult patient receiving greater than or equal to 300 mg/day phenytion and showing phenytoin levels less than or equal to 5 ug/ml should be investigated for possible noncompliance before altering their dosage schedules.