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Epileptic seizures are disorders of the brain caused by short-lasting increased discharges of nerve cells. Epilepsy exists when epileptic seizures occur repeatedly without a recognizable explanation for the time of occurrence – exceptionally even after a first seizure if there is a high risk of further seizures.

There are more than ten forms of epileptic seizures and many more forms of epilepsy, partly because they can be associated with a combination of different types of seizure. Each affected person usually has only one form of epilepsy with one to three types of seizures. The intervals between individual seizures can vary from seconds to years or even decades.

The word epilepsy comes from the Greek and means “to be seized”, “to be seized” or “to be affected or seized by something”. Until the Middle Ages, epilepsies were referred to as “morbus sacer” or “holy disease”, giving them a special status that they still sometimes have today. A generally valid description of epileptic seizures that applies to all forms of seizures could be as follows: Epileptic seizures are relatively short-lasting, sudden changes in consciousness, thinking, behavior, memory, feeling or sensation or muscle tension due to a temporary dysfunction of nerve cells in the brain, which discharge electrically in an increasing and accumulating manner. Although this definition is correct, it is far too long to remember and use in everyday life. For this reason, epileptic seizures can also be defined in simplified terms as the expression of a temporary functional disorder of nerve cells, whereby the effects depend on the tasks that the nerve cells involved normally have.1

1. What are epileptic seizures and epilepsies? Flyer of the Swiss Epilepsy League. [retrieved on 04.12.2023]

All epilepsies are based on changes in the brain that lead to an increased susceptibility to seizures. Various diseases can trigger epileptic seizures and epilepsies. An increased predisposition to epileptic seizures can be congenital, inherited or acquired through illness or injury. Seizures and epilepsies can occur at any age, but are more frequent at certain stages of life. Not to be confused with the causes are factors that can also trigger epileptic seizures in people without epilepsy (so-called occasional seizures) – for example alcohol withdrawal or high fever in children.

Today, the cause of epilepsy can be identified in around 60% of cases. However, the cause of epilepsy often remains unclear despite comprehensive diagnostics.1

Epilepsies are initially classified according to seizure type:1

Focal seizures
Focal seizures begin in a circumscribed section of the brain, for example in a part of the temporal lobe or in the frontal lobe. Some of them are also limited to this section. They can occur with or without impaired consciousness and can take very different forms. Some of them are barely noticeable to strangers.

In the case of unconsciously experienced seizures, those affected appear absent-minded, detached without normal contact, as if in a trance or dream; the affected person then has a memory gap for what has happened.1

Generalized seizures
In this type of seizure, large areas of the brain in both hemispheres (bilateral) are affected from the outset. The seizures are usually accompanied by a complete loss of consciousness (exception e.g. myoclonus, see below). Generalized seizures vary greatly in their outward appearance. The spectrum ranges from barely noticeable absences to threatening tonic-clonic seizures.1

A special case: Lennox-Gastaut syndrome
Lennox-Gastaut syndrome (LGS) is one of the most severe epileptic and developmental encephalopathies. It accounts for 1-10% of all childhood epilepsies. There are several co-occurring seizure types, including sudden drop seizures (brief tonic or atonic seizures) with a high risk of injury, atypical absences that may progress to non-convulsive status epilepticus, and other seizure types that are focal, generalized, tonic-clonic, or unilateral clonic. The predominant type of seizure may change over time. LGS is always associated with cognitive decline, often severe behavioral disorders and drug resistance. The onset of the disease is usually before the age of 8, with a peak between 3 and 5 years.2

1. Causes of epilepsy. Flyer of the Swiss Epilepsy League. [retrieved on 23.02.2024].
2. Kröll, J. / Datta, A.N. Neue Therapien bei pädiatrischen Epilepsien. Neuropediatrics. 17.09.2021 [retrieved on 23.02.2024].

Careful diagnosis is a prerequisite for successful epilepsy treatment.

The spectrum of manifestations of epilepsy is wide. Good diagnostics are therefore essential in order to differentiate epilepsy from other clinical pictures such as brief unconsciousness due to reduced blood flow or psychogenic seizures. The diagnosis should be made or verified by a specialist experienced in the treatment of epilepsy. Treatment should only be started once the diagnosis of epilepsy has been established beyond doubt.

When making a diagnosis, the specialist is dependent on the active cooperation of the affected person, because in addition to precise neurological examinations, it is particularly important to take a detailed history of the illness with a detailed description of the seizures and their occurrence over time.1,2 A seizure diary, for example, can be helpful, in which the occurrence and type of seizures can be recorded.

The following examination methods can be used:

  • Electroencephalography (EEG): Electroencephalography is used to measure and record brain waves, i.e. the electrical activity on the surface of the brain.3
  • Computed tomography (CT): This X-ray procedure makes it possible to visualize human body structures such as the brain and skull in detail in cross-sectional images.2
  • Magnetic resonance imaging (MRI): Magnetic resonance imaging uses magnetic fields and radio waves to visualize organic changes in the brain.4

1. Schüler P, Informationszentrum Epilepsie (ize) der Dt. Gesellschaft für Epileptologie e.V. (Hrsg.). Erhebung der Krankengeschichte, Informationsblatt 051, 2008. Berlin: Dt. Gesellschaft für Epileptologie e.V. [retrieved on: 13.02.2024].
2. Schüler P, Informationszentrum Epilepsie (ize) der Dt. Gesellschaft für Epileptologie e.V. (Hrsg.). Nicht-invasive Verfahren ausser EEG, Informationsblatt 052, 2008. Berlin: Dt. Gesellschaft für Epileptologie e.V. [retrieved on: 13.02.2024].
3. Penin H, Fröscher W, Informationszentrum Epilepsie (ize) der Dt. Gesellschaft für Epileptologie e.V. (Hrsg.). Elektroenzephalographie (EEG), Informationsblatt 055, 2010. Berlin: Dt. Gesellschaft für Epileptologie e.V. [retrieved on: 13.02.2024].
4. Schumacher M, Informationszentrum Epilepsie (ize) der Dt. Gesellschaft für Epileptologie e.V. (Hrsg.). Magnetresonanztomographie (MRT), 2004. Berlin: Dt. Gesellschaft für Epileptologie e.V. [abgerufen am: 13.02.2024].

The aim of any epilepsy therapy is to achieve freedom from seizures.

It is not always possible to control epilepsy. With some types of epilepsy, 90 percent of those affected are seizure-free, with others, a maximum of 10 to 20 percent. Almost two thirds of people with epilepsy lead a normal life, i.e. they do not need any other help apart from their daily medication and medical care1.

Drug therapy
Almost all people with epilepsy are treated with medication. Once epilepsy has been diagnosed, treatment by a neurologist usually consists of taking medication to suppress the seizures (“seizure-suppressive medication”, ASM for short, or “anticonvulsants”, formerly also known as “antiepileptic drugs”). Which medication, whether one or several substances, depends on the form of epilepsy and other factors, e.g. concomitant diseases1. Depending on the individual response, the dosage is gradually adjusted until no further epileptic seizures occur or until unacceptable side effects occur.1 If seizure freedom cannot be achieved with monotherapy(ies), the next step is usually to use two drugs in a combination therapy. Around a third of all epilepsy patients do not achieve freedom from seizures, even with a combination therapy with several medications.2,3 In order to help these patients, Eisai scientists are constantly researching new therapeutic approaches.

Epilepsy surgery
For some patients who are not seizure-free, surgery is an option for the treatment of epilepsy. In some cases, however, drug treatment must be continued even after successful epilepsy surgery.4 Epilepsy surgery is performed at specialized epilepsy clinics.

Neurostimulation
Under certain circumstances, neurostimulation as a further therapy option can lead to an improvement in the seizure situation. Parts of the brain itself (deep brain stimulation) or fiber pathways that lead there (e.g. the vagus nerve) are stimulated with a low current.5

Ketogenic diet
In addition to drug therapy, it may be advisable to follow a ketogenic diet: A diet low in carbohydrates but high in protein and fat can reduce the frequency of seizures.6

1. treatment of epilepsy – Swiss Epilepsy League [accessed 13.02.2024].
2. epilepsy in adults: Treatment with medication (gesundheitsinformation.de), Foundation for Quality and Efficiency in Health Care (IQWiG). Berlin [retrieved on: 04.12.2023].
3. Fröscher W, Informationszentrum Epilepsie (ize) der Dt. Gesellschaft für Epileptologie e.V. (Hrsg.). Schwer behandelbare Epilepsie, Informationsblatt 079, 2012. Berlin: Dt. Gesellschaft für Epileptologie e.V. [accessed on: 04.12.2023].
4. Epilepsiechirurgie bei Erwachsenen – Deutsche Epilepsievereinigung (epilepsie-vereinigung.de), Berlin: Deutsche Epilepsievereinigung. [abgerufen am: 04.12.2023] .
5. Neurostimulation in the treatment of epilepsy – Deutsche Epilepsievereinigung (epilepsie-vereinigung.de), Berlin: Deutsche Epilepsievereinigung. [retrieved on: 04.12.2023].
6. Ketogenic diets – German Epilepsy Association (epilepsie-vereinigung.de) Berlin: German Epilepsy Association. [abgerufen am: 04.12.2023].

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