What causes epileptic seizures?

From the Guidelines

Seizures are caused by abnormal excessive or synchronous neuronal activity in the brain. This definition, as stated by the International League Against Epilepsy (ILAE), highlights the complex and not fully elucidated mechanism of epileptic seizures 1. The classification of seizures is operational and not based on fundamental mechanisms, which can make diagnosis and treatment challenging.

Classification of Seizures

Seizures can be classified into three main categories: focal onset, generalized onset, or unknown onset 1.

• Focal seizures arise within networks of a single cerebral hemisphere and may remain localized or become more widely distributed.
• Generalized seizures rapidly affect both hemispheres and both sides of the body.
• Unknown onset seizures are those that cannot be classified into either focal or generalized categories.

Causes of Seizures

Various factors can contribute to the development of seizures, including:

• Genetic conditions
• Brain injuries, such as traumatic brain injury (TBI)
• Infections
• Stroke
• Brain tumors
• Developmental disorders
• Certain medical conditions, like epilepsy, which affects approximately 1.2% of the United States population 1

Management of Seizures

For individuals with known seizure disorders, treatment typically involves anticonvulsant medications, which help stabilize electrical activity in the brain. Identifying and avoiding specific triggers can also help manage seizure frequency. The most effective approach to managing seizures is to individualize treatment based on the specific medication, seizure type, and patient characteristics.

From the Research

Causes of Seizures

There are no direct research papers provided to answer the question of what causes seizures. However, the provided studies discuss various antiepileptic drugs and their effectiveness in treating different types of seizures.

Types of Seizures and Their Treatment

• Focal onset seizures:
  • Lamotrigine, levetiracetam, and carbamazepine are effective treatments 2
  • Oxcarbazepine, topiramate, gabapentin, and phenytoin are also used, but may have varying degrees of effectiveness 2
• Generalized tonic-clonic seizures:
  • Sodium valproate is a commonly used treatment, but lamotrigine and levetiracetam may be suitable alternatives 2, 3
  • Valproate, ethosuximide, and lamotrigine are effective for absence seizures 3
• Status epilepticus:
  • Benzodiazepines, such as lorazepam and midazolam, are first-line treatments 4
  • Intravenous administration of valproic acid and levetiracetam may also be effective 5

Antiepileptic Drugs

• Carbamazepine and oxcarbazepine are still widely used and effective treatments for focal-onset epilepsy and primary generalized tonic-clonic seizures 6
• Newer antiepileptic drugs, such as levetiracetam and lamotrigine, may have improved efficacy and tolerability profiles compared to older drugs 2, 3
• Benzodiazepines, such as clobazam and clonazepam, may be used for seizure prophylaxis in patients with refractory epilepsy 4