Epileptic seizures are caused by a disturbance in the electrical activity of the brain. There are many different types of epileptic seizure. Any of us could potentially have a single epileptic seizure at some point in our lives. This is not the same as having epilepsy, which is a tendency to have seizures that start in the brain.
Are all seizures the same?
There are different types of epileptic seizures, but they all start in the brain. There are other types of seizures which may look like epileptic seizures but they do not start in the brain.
Some seizures are caused by conditions such as low blood sugar (hypoglycaemia) or a change to the way the heart is working. Some very young children have 'febrile convulsions' (jerking movements) when they have a high temperature. These are not the same as epileptic seizures.
On this page when we use the word ‘seizure’ we mean epileptic seizure.
Types of seizures
There are two main types of seizure, focal and generalised. Whether you, or someone you know, has had a single seizure or has been diagnosed with epilepsy, it may help to identify the type of seizures that are relevant to you, and how they affect you.
How epilepsy is described
You may see epilepsy described in two ways. One way describes the type of epilepsy, the other describes the type of seizure.
The type of epilepsy depends on the cause of the epilepsy. For example, 'symptomatic epilepsy' means there is a known cause (such as a brain injury) and 'idiopathic epilepsy' means that the epilepsy is usually genetic or inherited.
The type of seizure depends on what happens to the person during the seizure. Here, we look at the types of seizures and not the types of epilepsy.
Triggers are situations that can bring on a seizure in some people with epilepsy. Some people's seizures are bought on by certain situations. Common triggers include lack of sleep, stress, alcohol, and not taking medication.
A person's seizures usually last the same length of time each time they happen and stop by themselves. However, sometimes seizures do not stop or one seizure follows another without the person recovering in between. If this goes on for 30 minutes or more it is called status epilepticus or ‘status’.
Status is not common, but it can happen in any type of seizure and the person may need to see a doctor. Status in a tonic clonic (convulsive) seizure is a medical emergency and the person will need urgent medical help. Do not wait until the seizure has lasted 30 minutes before calling for an ambulance.
Keeping a regular record of your seizures helps to monitor your triggers and helps medical staff review your treatment. We have paper, PDF and an app version of a seizure diary you can use.
Neurones and the brain
Neurones normally communicate by using electrical and chemical signals or messages that cause ‘depolarisation’. But sometimes neurones might send out an ‘abnormal’ message.
Free smartphone app
Our free smartphone app contains seizure management tools, including a seizure diary to help you monitor your triggers. It is available on both iPhone and Android phones.
This information was taken from our seizures leaflet.