Abstract:

Therapeutic monitoring of antiepileptic drug plasma levels is an important tool in the management of epilepsy, but it needs to be applied intelligently, as it otherwise can easily become counterproductive. The present article discusses the significance of low, average and high reference ranges, and typical mistakes derived from their misunderstanding (dose decrease in perfectly well-treated patients because of a high level; unnecessary dose increase in seizure free patients because of low levels; failure to increase dose in uncontrolled patients because of a level “in the therapeutic range”). “Therapeutic range” should never be applied in general but only with respect to individual patients. The necessity is highlighted of establishing an individual therapeutic level as a reference for all later issues that might arise.Aspects of particular practical importance such as the role of plasma levels for the assessment of adherence and the establishment of pharmacoresistance are discussed in more detail.

Keywords:

Non-adherence, Pharmacoresistance, Enzyme-induction, Reference Ranges, Breakthrough Seizures, Seizure Control, Antiepileptic Drug Toxicity