Therapeutic drug monitoring of valproic acid

The unpredictable and unfavorable connection of dose and plasma concentration of valproic acid supports the necessity to regularly measure its plasma concentration. The present study is drug monitoring of valproic acid and comparative evaluation of therapeutic monitoring results of valproic acid for assessment of clinical response, safety and toxicity in different age and gender groups of Chinese epileptic patients. This knowledge will help the clinicians in adjusting the drug dosages of valproic acid in various sub-groups of epileptic patients for enhancing the safety and minimizing the toxicity of valproic acid. A total of 206 plasma samples (126 males and 80 females) of epileptic patients using valproic acid were requested for therapeutic drug monitoring by neurology department of Qilu Hospital. It was found that 29 % of the total samples were found in sub-therapeutic levels, 13% of the samples had toxic levels and 58% of all the samples had valproic acid levels in therapeutic range. The difference in plasma concentration of valproic acid is notably altered in gender and various age groups. However, this requires further investigation. Despite the majority of samples in the therapeutic range, there was an unfavorable clinical response. The outcomes of the current research work exposed that there was a poor correlation between the plasma concentration and clinical response. Careful attention must be applied to specific gender and particular age group on an individual basis in the interpretation of plasma concentration results, in order to facilitate the modification of doses and develop the best approach in treatment and to obtain the desired clinical response because multiple factors can affect the valproic acid plasma concentration. Through these results, it can be concluded that poor correlation exists between valproic acid plasma concentration and clinical response.