Epilepsy
Evaluation
General—recurrent seizures secondary to acquired or genetic brain disorder
Epidemiology—2 million in the United States have epilepsy.
Diagnostic algorithm
Determine whether or not the patient has seizures.
Exclude migraine, syncope, transient ischemic attack, psychogenic, movement disorders, and so on.
Determine the underlying cause for seizures.
Consider family history, central nervous system (CNS) trauma, sinus infection, drug abuse, cancer, and so on
Complete evaluation includes electrolytes, liver function tests (LFTs), drug screen, electroencephalogram (EEG), magnetic resonance imaging (MRI), lumbar puncture. (see Table 2.26.1)
Treatment
General Guidelines
Initial adverse effects include sedation, dizziness, ataxia, headache, and nausea.
Adjust the dose of antiepileptics to limit toxicity and to obtain the best control of seizures.
Most antiepileptics can cause a rash which in some becomes Stevens-Johnson syndrome.
Least likely to cause rash are divalproex, gabapentin, and levetiracetam
Add a second-line agent if seizures are not fully controlled with the maximum dose of the first-line agent.
If after 2 years the patient is seizure-free, withdrawal of the medication can be considered.
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In most states, licensed drivers must report a seizure condition to the Department of Motor Vehicles (DMV).
Requirements are available from the Epilepsy Foundation at www.efa.org.
First-line medications
Therapeutic range—not established
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Special considerations
Phenytoin toxicity (death can result from respiratory or cardiovascular collapse)
Dizziness, confusion, ataxia, tremor, nystagmus, blurry vision
Dysarthria or slurred speech
Nausea, vomiting
Hyperreflexia
Hypotension
