Antiepileptic TDM pattern at a tertiary care hospital in India

Therapeutic drug monitoring, a comparatively new investigational procedure in clinical pharmacology, is considered very beneficial to epilepsy patients though it increase the health care cost. Aim of this study was to determine the pattern of use of antiepileptic drug level monitoring over the last 7 years in our tertiary care centre and to critically comment on its utility. Retrospective data audit of archived data from 1998 to 2004 and age, sex, estimated levels of phenytoin, carbamazepine and phenobarbitone by HPLC were noted down, tabulated and compared. Chi square test was used for analysis. Three thousand five jundred thirty four blood samples of patients requesting for 4213 estimations of phenytoin, phenobarbitone or carbamazepine were received. Among the obtained samples, 44.0% (1058) were of children, 68.0% (2402) were of males, 0.6% (22) patients were getting 3 and 18.0% (635) getting 2, antiepileptic medications. 13.0% (546) samples showed level in the toxic range and 39.0% (1653) in lower range. There was increasing demand observed for estimation of antiepileptic drugs, over the 7 years. The number of abnormal values of phenytoin, phenobarbitone and carbamazepine did not show any significant difference over the years. The pattern was similar to that observed in other countries.