Epilepsy Management - Key Issues, Challenges, and Developments
Epilepsy Management - Key Issues, Challenges, and Developments
Across all ages, at a considerable expense of emotional and financial resources to society, epilepsy holds a significant share of neurological morbidity and mortality. Fortunately, the management of epilepsy has evolved due to great developments in the understanding of the pathogenesis of the disease, improvement in the tools for evaluation, and the availability of newer pharmacological and non-pharmacological measures for its treatment. This has resulted in better seizure control and improvement in quality of life (QOL) for a much larger number of afflicted individuals.While concepts in the pathogenesis of the disease are a key building block, the purpose of this review is to focus on the novel aspects of evaluation and management.
Therapy of epilepsy is based on a correct diagnosis of the epilepsy syndrome, appropriate choice of medication(s), early identification of medically refractory epilepsy, and consideration of epilepsy surgery in ideal surgical candidates. Among the options available in clinical practice, anti-epileptic medications and epilepsy surgery form cornerstones in epilepsy management; vagus nerve stimulation and ketogenic diet are the other two considerations that may benefit some individuals in whom good surgical or medication options do not exist. Other forms of magnetic or electrical stimulation of the brain do not have clearly defined roles yet.
Anti-epileptic Medication
Prior to 1990, there were only six major anti-epileptic drugs (AEDs) available for controlling seizures. These included carbamazepine (CBZ), phenytoin (PHT), phenobarbital (PB), primidone (PRM), valproic acid (VPA), and ethosuximide (ESM).These medications are effective and are still used in patients with epilepsy; however, as a group, they share some disadvantages. They have significant influence on hepatic enzymes (induction or inhibition), which lead to important interactions with commonly used medications as well as complications if combination AED therapy is warranted. Rapid metabolism of vitamin D and other steroid hormones due to hepatic induction may also lead to adverse effects in reproductive and bone health. The last decade has seen an unveiling of nine new antiepileptic medications in the quest of newer and safer treatment options. Eight of them (gabapentin (GBP), lamotrigine (LTG), levetiracetam (LEV), topiramate (TPM), tiagabine (TGB), oxcarbazepine (OXC), zonisamide (ZNS), and felbamate (FBM)), with the exception of vigabatrin (VGB), have been approved by the US Food and Drug Administration (FDA) and are available for use in the US. All of these medications are indicated as add-on therapy in the treatment of epilepsy and there is gathering evidence supporting their use as monotherapy in select clinical syndromes. Indications for their use in pediatric age groups are also forthcoming due to a concerted effort to increase their availability across all age groups. In contrast to the older anti-epileptic medications, the newer agents share a more favorable side effect profile. The efficacy is not vastly different; however, a smaller risk of adverse effects give these medications a valuable role while formulating a management plan tailored toward the unique needs of any particular patient.
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