What is the management of seizures in adults?

Management of Seizures in Adults

Immediate Emergency Management

For adults presenting with active generalized convulsive seizures, administer benzodiazepines as first-line treatment, and if seizures persist despite optimal benzodiazepine dosing, immediately give fosphenytoin, levetiracetam, or valproate as second-line agents—all three have equivalent efficacy. 1, 2

First-Line Treatment: Benzodiazepines

• Benzodiazepines are the established first-line treatment for active seizures and status epilepticus 1, 2
• During administration, maintain an unobstructed airway, continuously monitor vital signs, and have artificial ventilation equipment immediately available 2
• Critical pitfall: Ensure optimal benzodiazepine dosing before escalating to second-line agents—inadequate first-line dosing is a common error 2

Second-Line Treatment for Refractory Seizures

If seizures continue despite appropriately dosed benzodiazepines, the 2024 ACEP guidelines provide Level A evidence that fosphenytoin, levetiracetam, or valproate should be administered with similar expected efficacy. 1, 2

• All three agents achieve seizure cessation and improved consciousness in approximately 45-47% of patients at 60 minutes 2
• Safety profile differences 1, 2:
  • Levetiracetam: 0.7% life-threatening hypotension, 0.7% arrhythmias, 20% intubation rate
  • Fosphenytoin: 3.2% life-threatening hypotension, 26.4% intubation rate
  • Valproate: 1.6% life-threatening hypotension, intermediate intubation rate

Evaluation of Underlying Etiology

Distinguish Provoked vs. Unprovoked Seizures

Immediately evaluate for acute symptomatic (provoked) causes, as these require simultaneous treatment of the underlying condition rather than chronic antiepileptic therapy. 1, 3, 4

• Provoked seizures occur within 7 days of an acute insult and include 1:

  • Electrolyte abnormalities (hyponatremia, hypoglycemia, hypomagnesemia)
  • Alcohol or drug withdrawal
  • Toxic ingestions
  • CNS infections (meningitis, encephalitis)
  • Acute stroke or CNS mass lesions

• Unprovoked seizures occur without acute precipitating factors or >7 days after a remote insult 1

Essential Diagnostic Workup

• Serum electrolytes, glucose, magnesium, hepatic and renal function 3
• Brain imaging (CT or MRI) to identify structural lesions 3
• Lumbar puncture when meningitis or encephalitis is suspected 3
• Consider non-convulsive status epilepticus in patients with unexplained confusion or coma—obtain EEG urgently 4

Decision to Initiate Antiepileptic Medication

For First Unprovoked Seizure in Adults

For adults with a first unprovoked seizure who have returned to baseline, antiepileptic medication initiation in the ED is generally NOT recommended unless specific high-risk features are present. 1

• Approximately one-third to one-half of patients will have recurrence within 5 years, but treatment does not improve long-term outcomes 5
• The number needed to treat to prevent one recurrence within 2 years is approximately 14 patients 5
• High-risk features warranting treatment consideration 5:
  • Remote history of brain disease or injury
  • Focal seizure onset
  • Abnormal EEG findings

For Provoked Seizures

Treat the underlying medical cause; most patients do not require long-term antiepileptic medication unless the predisposing factor is uncorrectable. 4

• Short-term anticonvulsant medication is appropriate during acute illness 3, 4
• Important exception: Phenytoin is ineffective for alcohol withdrawal seizures and for seizures due to theophylline or isoniazid toxicity 4
• Explain to patients and families that provoked seizures do not constitute epilepsy 4

For Known Epilepsy with Breakthrough Seizures

For patients with established epilepsy who missed doses or have subtherapeutic levels, administer additional doses of their regular medication; loading doses can be given with minimal toxicity in tolerant patients. 3

Medication Selection for Chronic Therapy

When Antiepileptic Medication Is Indicated

Levetiracetam is a reasonable first choice for partial onset seizures in adults, with initial dosing of 500 mg twice daily, titrating by 1000 mg/day every 2 weeks to a target of 3000 mg/day. 6

• Levetiracetam is FDA-approved as adjunctive therapy for partial onset seizures in adults 6
• Maximum recommended dose is 3000 mg/day; higher doses have not shown additional benefit 6
• Can be administered with or without food 6

For Myoclonic or Primary Generalized Tonic-Clonic Seizures

Start levetiracetam at 1000 mg/day (500 mg BID), increasing by 1000 mg/day every 2 weeks to the recommended 3000 mg/day. 6

• The effectiveness of doses lower than 3000 mg/day has not been adequately studied for these seizure types 6

Monitoring and Follow-Up

Immediate Post-Seizure Period

• Continue observation for recurrence, particularly during the first 6 hours when early recurrence risk is highest 5
• Monitor for adverse effects from administered medications 2
• Ensure patients do not leave the ED until they have returned to baseline mental status 1

Ongoing Management Considerations

• Complete seizure control should be the goal, as uncontrolled seizures carry significant risks including 4-7 times higher mortality, substantial injury rates, and impaired quality of life 7
• After failure of 2 appropriate antiepileptic drugs, patients are considered medically refractory and should be referred to a certified epilepsy center for evaluation of surgical, dietary, or device therapies 8

Critical Pitfalls to Avoid

• Inadequate benzodiazepine dosing before escalating to second-line agents 2
• Failure to identify and treat underlying causes such as metabolic abnormalities, infections, or structural lesions 2
• Insufficient monitoring after apparent seizure cessation—patients require continued observation 2
• Using phenytoin for alcohol withdrawal seizures—it is ineffective for this indication 4
• Initiating long-term antiepileptic therapy for provoked seizures when the underlying cause is correctable 4