PRACTICE RECOMMENDATIONS
• Prescribe an antiepileptic drug (AED) after a first unprovoked seizure only if the seizure was prolonged or there is a risk of recurrence. C
• Use monotherapy whenever possible; if seizures continue and potential adverse effects prevent an increase in dosage, switch to a different AED and taper off the first agent. A
• Consider gradual withdrawal of AEDs from patients who have been seizure-free for 2 to 5 years. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
CASE Joe G, a 44-year-old man who has been your patient for years, comes to your office 48 hours after having a seizure. He has no history of seizures, had no warning signs or symptoms, and felt fine all day, but simply collapsed when the seizure occurred. He was transported to the emergency department (ED), and found to be postictal, with no further seizure activity. The ED work-up included a hemogram, comprehensive metabolic panel, and computed tomography brain scan, all of which were normal. An hour later, Joe had a normal neurological exam, then underwent electroencephalography (EEG) and magnetic resonance imaging (MRI) and was discharged home without medication.
How would you treat this patient?
About 10% of Americans will experience a seizure at some point in their lives,1,2 and more than 3 million have epilepsy.3 The incidence ranges from 1% among 20-year-olds to more than 3% by the age of 75.1,2
To adequately care for such patients—whether they have had multiple seizures or only one—you need to know whether they’re at risk for recurrences, when (or if) to prescribe an AED, and which agents provide optimal seizure control with the fewest adverse effects. You also need to know when a referral to an epilepsy specialist is indicated, when or whether it’s safe for patients to stop taking antiseizure medication, and how to address lifestyle issues that patients with epilepsy often need help with.
This review addresses these and other questions.
Is it epilepsy? How to respond to a single seizure
A seizure—a transient occurrence of signs or symptoms due to abnormal excessive or synchronous neural activity in the brain—can be either focal (partial) or generalized. In addition, seizures can be broadly divided into 2 categories, based on etiology:
Provoked seizures are caused by an acute structural, toxic, or metabolic insult to the brain, and, presumably, would not have occurred if the underlying medical condition did not exist. Treating the cause—eg, alcohol withdrawal, hyponatremia, or hypoglycemia—should prevent a recurrence.
Unprovoked seizures have no apparent underlying cause. Epilepsy is defined as a chronic condition characterized by ≥2 unprovoked seizures at least 24 hours apart, and epilepsy syndromes are classified as localization-related or generalized (TABLE 1).1,4,5
Generally, epileptologists do not recommend symptomatic treatment of a first unprovoked seizure6—a consensus based on several randomized controlled trials that found immediate treatment with an AED reduced the risk of a subsequent seizure in the short term, but did not affect long-term outcomes or the development of epilepsy.7
Treatment should begin after a single seizure, however, if the seizure was prolonged or there is an increased risk of recurrence.6 Factors that increase this risk include an abnormal EEG, particularly if the abnormality is epileptiform; the presence of a brain lesion; a localized (focal) seizure; and an abnormal neurologic exam.8 A history of status epilepticus—a single, unremitting seizure lasting ≥5 to 10 minutes or frequent seizures without a return to neurologic baseline in between—or complex febrile seizures, and a family history of epilepsy are risk factors for recurrence, as well.7
When the patient is a child. Prescribing an AED for a child after a first unprovoked seizure is not indicated to prevent the development of epilepsy, but may be considered, as for adults, in circumstances where the benefit of reducing the risk of a second seizure outweighs the risk of pharmacologic and psychosocial adverse effects.9
CASE Joe’s ED records show that his MRI was normal, but his EEG revealed an epileptogenic focus on the right temporal region—a finding that indicates that he has an elevated risk of recurrence and is a candidate for an AED. Before selecting a particular agent, you review his chart.
Joe is taking a thiazide diuretic and a calcium channel blocker for hypertension. He was a heavy drinker until he had an episode of pancreatitis 10 years ago, and has been abstinent ever since. About 5 years ago, he suffered from depression and was treated with sertraline, but the depression resolved and the drug was discontinued 3 years ago. The patient’s mother and brother have type 2 diabetes and his father had a myocardial infarction before the age of 60. Joe was laid off from his sales job 18 months ago and is actively seeking employment. At this point, you consider a broad-spectrum AED that would not interact with his current medications or adversely affect his medical conditions, and would be relatively inexpensive.