Pathophysiology of Antiepileptic Drug Refractoriness
Introduction and Definitions
Drug refractoriness is a serious problem in the treatment of patients with epilepsy with devastating consequences on the patient’s quality of life. In about one-third of epileptic patients severe seizures persist despite syndrome-appropriate medical treatment (French 2007). Prediction of refractory epilepsy is a complex issue for the physician managing patients with epilepsy, because multiple mechanisms appear to contribute to this clinical phenomenon (Löscher and Potschka 2005; Löscher et al. 2009). Thus, understanding drug refractoriness in epilepsy represents a challenge for both experimental and clinical research.
This chapter will briefly address the experimental and clinical evidence on mechanisms underlying drug refractoriness and factors that regulate them. The emphasis will be on the two major concepts that have been put forward to explain drug refractoriness: the target- and the transporter-hypothesis (Loscher and Potschka 2005; Remy and Beck 2006...
KeywordsGABAA Receptor Temporal Lobe Epilepsy Efflux Transporter Focal Cortical Dysplasia Refractory Epilepsy
List of Abbreviations
Breast-cancer resistance protein
Focal cortical dysplasia
Malformations of cortical development
Multidrug resistance-associated proteins
Temporal lobe epilepsy
Volumes of interest
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