Carbamazepine and lamotrigine plasma concentrations in epileptic patients during optimising therapy

Therapeutic monitoring of antiepileptic drugs is important in process of optimisation of therapy of epileptic patients. Carbamazepine (CBZ) and Lamotrigine (LMT) are important drugs in therapy of epileptic patients which requires the monitoring of concentration of these drugs in serum. Ourstudy aim was the comparison and interpretation of the results of routine therapeutic monitoring of Carbamazepine and Lamotrigine in spotlight of antiepileptic therapy optimisation. We have analyzed 74 blood samples of epileptic patients who were in therapy with Carbamazepine or Lamotrigine. High pressure liquid chromatographywas used in determiningthe serum concentration of above mentioned drugs. Results of our study show the positive correlation between dosage and serum concentration of CBZ. (r = 0.78). The correlation coefficient between the dosage and serum concentration of LMT is higher than CBZ (r = 0.825). In the process of monitoring of serum concentration of CBZ, very important issue is the serum concentration of active metabolite named to carbamazepine-10,11-epoxide (CBZE). The correlation coefficient between the CBZ and its active metabolite was r = 0.57. During analysis of correlation between blood sampling time from last dose intake and serum concentration of respective drug in both drugs (CBZ and LMT) we have found the negative small correlation (r = -0.256 and r = -0.288). The results of our study contribute to other studies which confirm the complexity of therapeutic drug monitoring (TDM) process in general and particularly for CBZ and LMT. The process of TDM requires the selection of adequate analytical method and right appropriate interpretation of the serum concentration of these drugs.