Antiepileptics

Antiepileptics are used to minimize or prevent seizures in individual diagnosed with epilepsy.

Epilepsy causes frequent seizures, uncontrolled muscle movements with or without loss of consciousness that can lead to serious complications.

There are many types of antiepileptics, and each works in a slightly different way and may have more or less side effects.

Antiepileptics often present numerous side effects, generally not severe. The most common ones are: sleepiness, dizziness, headache, fatigue, mood swings, and many others.

Antiepileptic drugs are usually prescribed following the occurrence of a second seizure, and treatment often involves long-term usage (for years) with a daily dose.

The optimal approach is to use a single antiepileptic drug at the lowest effective dose that achieves the desired outcome without reaching toxic levels.

Therefore, regular blood tests are conducted to measure drug levels to keep seizures controlled without health risks.

The selection of the appropriate drug is based on the specific type of seizure experienced.

Other factors that should be considered are:

• The age of the patient.
• Specific syndromes known to respond well to a particular medication.
• Existing conditions affecting the kidneys, liver and heart.
• Concurrent physical ailments and mental health disorders.
• For women, the possibility of pregnancy.

There are different treatments to manage seizures in emergency situations compared to long-term management of epilepsy.

Based on the classification of epileptic seizures, the following groups are identified to determine the appropriate antiepileptic medication for long-term treatment:

The general properties of the antiepileptic drugs currently used are described below:

• Hydantoins

  • Phenytoin: Effective against focal and generalized tonic-clonic seizures but not for absences. It is also used to prevent seizures after brain surgery and in urgent cases like status epilepticus or status seizure.

• Benzodiazepines: Examples: Diazepam, Lorazepam, Clobazam and Clonazepam. They are used primarily as sedatives and anxiety treatments. However, they are approved as antiepileptics for emergency use in conditions like status epilepticus. Additionally, they are approved for specific disorders such as Lennox-Gastaut syndrome and myoclonus.

• Anticonvulsant barbiturates

  • Phenobarbital: Effective against focal seizures but less commonly prescribed due to its sedative effects.
  • Primidone: Used in focal seizures and often induces significant drowsiness.

• Iminostilbenes

  • Carbamazepine: Widely utilized for various tonic and tonic-clonic seizures, along with treating trigeminal neuralgia.
  • Oxcarbazepine: Effective in treating both focal and generalized seizures in epilepsy, and also prescribed for bipolar disorder.
  • Eslicarbazepine: Known for its efficacy against focal epilepsies.

• Succinimides

  • Ethosuximide: Specifically employed to prevent absence seizures, which are frequently in children characterized by loss of consciousness while their eyes seem fixed on a particular point.

• Other antiepileptic drugs

  • Acetazolamide: Primarily employed in managing absence seizures.
  • Valproate: Effective against both absence and tonic-clonic seizures, widely prescribed. However, caution is advised for women likely to conceive due to potential severe congenital defects in the brain and spinal cord of the baby.
  • Cannabidiol: Used for Dravet and Lennox-Gastaut Syndromes.
  • Felbamate: Used in very specific cases that are difficult to handle due to its potential toxicity.
  • Fenfluramine: Used in the genetic disorder known as Dravet syndrome.
  • Gabapentin and Pregabalin: Originally designed for epilepsy treatment, Gabapentin is also used for chronic neuropathic pain (such as painful diabetic neuropathy or post-herpetic neuralgia). Pregabalin, a more potent version of Gabapentin, is used for chronic pain resulting from nerve damage and as an adjunctive therapy alongside other antiepileptics for refractory partial epilepsy.
  • Lacosamide: It is only available in the United States and used for focal seizures.
  • Lamotrigine: Shares similarities with phenytoin and is especially effective for generalized epilepsy and Lennox-Gastaut syndrome.
  • Levetiracetam and brivaracetam: Typically prescribed for challenging-to-manage epilepsies in combination with other medications.
  • Perampanel: Used as an adjunctive therapy for focal seizures.
  • Rufinamide: Used in Lennox-Gastaut syndrome.
  • Stiripentol: Primarily used in severe myoclonic epilepsy (Dravet syndrome) in children when clobazam and valproate fail to provide adequate control.
  • Tiagabine: Supplementary treatment for challenging-to-manage focal seizures.
  • Topiramate and Cenobamate: Topiramate, aside from treating epileptic seizures in adults and children over 6 years, is also employed for prophylactic migraine treatment. Similar to phenytoin but with fewer side effects, it is especially useful in focal seizures and Lennox-Gastaut syndrome.
  • Vigabatrin: Used in epilepsies that are difficult to manage and infantile spasms.
  • Zonisamide: Prescribed in specific instances for adults with newly diagnosed focal epilepsy or as an addition to existing therapies.

Oral, nasal or rectal benzodiazepines administered as soon as possible are the most recommended medications in case of emergency.

In the hospital and when seizures last for a long time, a benzodiazepine is usually combined with another medication, which may be valproate or levetiracetam. However, protocols can significantly differ based on the specific case.

Should seizures persist despite two medication attempts, the necessity to anesthetize the individual may arise, followed by stabilizing them in an Intensive Care Unit (ICU).