Publication: Therapeutic Drug Monitoring of Antiepileptic Drugs at a Tertiary Care Hospital of Eastern Nepal
Date
2019
Journal Title
Journal ISSN
Volume Title
Publisher
Kathmandu University
Abstract
ABSTRACT
Background
Therapeutic drug monitoring (TDM) is the process of measuring drug level in body
fluids. It is done to maintain plasma concentration of the drug under therapy within
a specific target range for maximum therapeutic efficacy without unnecessary
exposure to adverse effects.
Objective
This study aims to evaluate necessity of therapeutic drug monitoring in Phenytoin,
Carbamazepine and Lamotrigine therapy among epileptic patients.
Method
A prospective, cross-sectional study was conducted for a period of one year at BP
Koirala Institute of Health Sciences, Dharan, Nepal. After taking detailed history,
blood samples were collected from epileptic patients on monotherapy with the
selected drugs. Plasma levels of these drugs were analyzed using High Performance
Liquid Chromatography technique (HPLC). Out of total 42 selected patients, 21 were
tested for phenytoin, 17 for carbamazepine and four for lamotrigine. The result was
categorized into therapeutic, sub-therapeutic and above-therapeutic groups based
on reference range.
Result
Out of total 21 samples tested for phenytoin, 15(71.4%) had plasma drug level within
therapeutic range, 5(23.8%) had within subtherapeutic range and 1(4.8%) had above
therapeutic range. Analysis of carbamazepine plasma level showed 14(82.3%) at
therapeutic level, 1(5.9%) at sub-therapeutic level and 2(11.8%) at above-therapeutic
level. Lamotrigine testing in four samples showed 2(50% in) both within therapeutic
range and above-therapeutic range.
Conclusion
Therapeutic drug monitoring of phenytoin, carbamazepine and lamotrigine showed
variation in plasma level irrespective of the therapeutic dose. It is suggested that
dose adjustment of antiepileptic drugs should be done after establishing ‘individual
therapeutic range’ following regular plasma monitoring.
KEY WORDS
Anti-epileptic, High performance liquid chromatography, Therapeutic drug monitoring
Description
Mandal NK,1 Rauniar GP,1 Rai DS,1 Pradhan B,2 Poudel P,3 Sapkota N4
1Department of Clinical Pharmacology and Therapeutics,
2Department of Internal Medicine,
3Department of Pediatrics and Adolescent Medicine,
4Department of Psychiatry,
BP Koirala Institute of Health Sciences, Dharan, Nepal.
Keywords
Anti-epileptic, High performance liquid chromatography, Therapeutic drug monitoring