All Causes of Seizures
Seizures are caused by a wide variety of conditions ranging from idiopathic cases to acute and chronic intracranial or systemic abnormalities, which require prompt identification and intervention to prevent morbidity and mortality. 1, 2
Classification of Seizures
- Seizures are classified as provoked (acute symptomatic) or unprovoked, with epilepsy defined as recurrent unprovoked seizures 2, 3
- Seizures represent an extremely heterogeneous group of medical conditions ranging from benign cases to life-threatening situations such as status epilepticus 1
- Approximately 10% of the population will have one or more seizures during their lifetime, with epilepsy affecting 1-3% of the population 3
Structural/Neurological Causes
- Brain tumors cause seizures in approximately 50% of patients, with partial seizures having the highest incidence 4
- Intracranial hemorrhage and perinatal ischemic stroke (10-12%) are common causes of neonatal seizures 1
- Hypoxic ischemic injury is the most common cause of seizures in both term and preterm infants (46-65%) 1
- Traumatic brain injury and cerebrovascular disease are common causes of acute symptomatic seizures 5
- Malformations of cortical development and other structural brain anomalies can cause seizures 1, 2
Metabolic and Systemic Causes
- Hypoglucemia is a significant metabolic cause of seizures 2
- Electrolyte imbalances can provoke seizures in patients without epilepsy 6
- Organ failure, particularly renal failure, can lead to seizures requiring control of blood pressure 6
Toxic/Substance-Related Causes
- Alcohol withdrawal and drug intoxications are common toxic causes of seizures 2, 6
- Medication-induced seizures account for approximately 6.1% of first-occurring seizures 7
- Common medications associated with drug-induced seizures include:
Infectious Causes
- Infections such as encephalitis can cause seizures 2
- Seizures occurring beyond the seventh day of life in neonates are more likely related to infections 1
Risk Factors for Drug-Induced Seizures
- History of epilepsy or previous seizures 7
- Cancer and blood-brain barrier dysfunction 7
- Concomitant neurological diseases or mental disorders 7
- Extremes of age (childhood, elderly) 7
- Fever and impaired liver or kidney function 7
- Polypharmacy and pharmacokinetic properties of medications 7
Treatment Approaches
- For provoked seizures, treatment should focus on relieving the provoking factor rather than initiating antiepileptic drugs 3
- Benzodiazepines are first-line treatment for drug-induced status epilepticus, with barbiturates and propofol as second-line options 7
- For epilepsy (recurrent unprovoked seizures), antiepileptic drugs are the standard treatment 3
- Selection of appropriate antiepileptic medication depends on seizure type, with drugs like levetiracetam indicated for:
- Phenytoin is ineffective for seizures secondary to alcohol withdrawal, theophylline, or isoniazid toxicity 6
Prevention of Drug-Induced Seizures
- Careful selection of optimal medication doses, especially in patients with impaired liver or kidney function 7
- Monitoring of blood parameters (liver enzymes, electrolytes, glucose) 7
- Monitoring blood plasma concentration of certain drugs 7
- Avoiding simultaneous administration of multiple CNS-stimulating drugs 7
- Rapid discontinuation of drugs that may be causing seizures 7
Special Considerations
- Non-convulsive status epilepticus should be considered in any patient with confusion or coma of unclear cause 6
- Antiepileptic drugs should be withdrawn gradually to minimize the risk of increased seizure frequency 8
- If trials of more than two antiepileptic drugs fail to control seizures, referral to an epilepsy center should be considered for evaluation of other treatment options, including epilepsy surgery 3