Understanding epilepsy
A clear, calm guide to what epilepsy is, why seizures happen, how they are diagnosed, and how monitoring can help you live more safely.
What is epilepsy?
Epilepsy is a non-communicable chronic condition that affects the brain, making it more likely for a person to experience repeated seizures.
A seizure happens when there is a sudden, brief burst of abnormal electrical activity in the brain, which temporarily changes what a person does, feels, or experiences.
Epilepsy can affect men and women equally. It can appear at any age and can look very different — from brief, subtle changes to more noticeable and complex episodes. How often seizures happen can vary a lot, from one seizure every few years to several in the same day.
According to the International League Against Epilepsy (ILAE), you need to have at least two seizures separated by 24 hours or more to be diagnosed with epilepsy. Sometimes these seizures won’t happen for many years, but if they are likely to recur within the next 10 years, they are considered epilepsy too. Epilepsy can be considered resolved if the person hasn’t had a seizure in the last 10 years and has been off epilepsy medication for 5 years or more. (ILAE, 2014)
Epilepsy in numbers
Epilepsy is one of the most common neurological conditions in the world. A clearer view of the scale helps put diagnosis and treatment in perspective.
Worldwide
WHO, 202650M
people are living with epilepsy globally, making it one of the most common neurological diseases.
5M
new cases are diagnosed each year worldwide.
70%
of people with epilepsy could live seizure-free with proper diagnosis and treatment.
Europe
WHO, 20266M
people are living with epilepsy in Europe.
300K
new cases are diagnosed in Europe every year.
0.5%
of the European population has epilepsy, while 4–5% will have a single seizure in their lifetime.
Specific populations — epilepsy can affect anyone, but certain age groups are more likely to develop it: infants and young children, especially in the first year of life; and older adults, particularly over the age of 65. (WHO, 2026)
Why does epilepsy occur?
There are many possible causes of epilepsy, but in about half of all cases the exact cause is unknown. (WHO, 2026)
Structural causes
Certain structural issues may increase the chance of seizures:
- Stroke, which can restrict the oxygen reaching the brain.
- Head injury.
- Brain malformations and congenital abnormalities.
- Scarring in areas of the brain.
Genetic causes
Some epilepsies run in families or are linked to specific gene variants. Genetic factors can directly cause epilepsy or increase a person’s susceptibility to it.
Infections
Certain brain infections — such as meningitis, HIV, or cysticercosis (a parasitic disease that can affect the brain) — can lead to epilepsy.
Understanding seizures
Seizures happen because of a sudden burst of excessive electrical activity in the brain. This activity disrupts the brain’s normal communication signals and leads to temporary changes in sensation, movement, awareness, or behaviour.
The ILAE notes that this abnormal activity may cause symptoms ranging from mild sensory changes to major motor movements. (Fisher et al. 2014)
What does a seizure look like?
Seizure symptoms vary widely. Depending on the part of the brain affected and how far the electrical activity spreads, a person may:
- Stare blankly (absence seizures).
- Appear confused.
- Lose awareness or consciousness.
- Fall or experience jerking movements.
- Feel intense emotions, such as fear or euphoria.
- Have unusual sensations.
Seizures are not always dramatic. Many involve convulsions, but a large proportion are subtle. (WHO, 2026)
Types of seizures
By origin and signs
The updated classification from the International League Against Epilepsy (ILAE, 2025) maintains four main seizure classes: focal, generalized, unknown (whether focal or generalized), and unclassified. (Beniczky et al. 2025)
Drug-resistant epilepsy
Around one third of patients do not respond to medication. The failure of two different medical strategies is considered drug-resistant epilepsy. (Lopez et al. 2015)
Medication is considered effective when there is a seizure-free period of typically 12 months, or at least three times longer than the longest seizure-free period before treatment. The probability of achieving seizure freedom decreases as the number of failed medications increases. (Perucca et al. 2023)
Managing drug-resistant epilepsy is an extra challenge: a wide variety of seizure types can be involved, and other health conditions can further limit the choice of medications.
How the type of seizure affects daily life
The type of seizures a person has can influence:
- What activities they can safely do — routine life, driving, sports.
- How much supervision they may need.
- The risk of falls or injuries.
- Sleep quality.
- Emotional wellbeing.
The benefits of advance detection
When seizures are detected early — through personal awareness, caregiver observation, or technology — patients can:
- Prepare, and sit or lie down safely.
- Reduce the risk of injury.
- Feel more in control.
- Maintain their independence.
- Improve their wellbeing and peace of mind.
Patients and families often report reduced anxiety when seizures feel less unpredictable.
What happens when epilepsy is suspected
A range of tests help identify not only the type of seizures, but also their possible causes.
Common diagnostic tests
They will help not only to find out the type of seizures, but also to know the possible causes:
Electroencephalogram (EEG)
An EEG measures brain activity and can show patterns linked to seizures. Small electrodes are attached to the scalp and connected to a recording device. The procedure is not painful. It may be routine or prolonged, and can take place at home (ambulatory) or in hospital — often combined with video monitoring. EEG is essential for diagnosis and classification. (Pellinen et al. 2024)
MRI or CT scan
These scans help identify underlying problems that might be causing epilepsy — such as scarring, tumours, strokes, or malformations — by providing structural imaging of the brain, as well as functional imaging that shows how the brain is working.
Blood tests
Blood samples can check for metabolic causes, such as low glucose or sodium levels, that might be related to seizures.
Genetic testing
Some types of epilepsy have genetic origins, such as a gene mutation, which may need to be ruled out.
Video-EEG monitoring
This combines video recording with EEG at the same time, used when a diagnosis is unclear or seizures are frequent.
Digital technology can support diagnosis with tools such as high-definition cameras, microphones, and machine-learning algorithms that help detect and differentiate epileptic from non-epileptic seizures. (Pellinen et al. 2024)
Why accurate diagnosis matters
Getting the right diagnosis helps to:
- Identify the appropriate treatment.
- Understand what to expect.
- Reduce unnecessary worry.
- Improve long-term outcomes.
Monitoring epilepsy
Once epilepsy is confirmed, your doctor may propose a plan that combines treatment, adjustments to daily life, and close monitoring.
Monitoring over time
Monitoring helps you and your doctor understand how your epilepsy evolves. Because seizure patterns change, monitoring can help:
- Track frequency and triggers.
- Assess how well medication is working.
- Identify sleep-related seizures.
- Detect prolonged or dangerous patterns.
- Improve safety at home and outdoors.
Monitoring matters at every age
- Children: may need supervision for safety and development.
- Adults: may want to track seizures for work, independence, or pregnancy planning.
- Older adults: may have other conditions that affect treatment and increase epilepsy-related risks, such as fractures after a fall.