In these seizures, you have epileptic activity in both hemispheres (halves) of your brain. You usually lose consciousness during these types of seizure, but sometimes it can be so brief that no one notices. The muscles in your body may stiffen and/or jerk. You may fall down.
The following is about the different types of generalised seizures. The list includes:
There are two phases in a tonic-clonic seizure: the ‘tonic’ phase, followed by the ‘clonic’ phase.
During the tonic phase, you lose consciousness, your body goes stiff, and you fall to the floor. You may cry out.
During the clonic phase, your limbs jerk, you may lose control of your bladder or bowels, bite your tongue or the inside of your cheek, and clench your teeth or jaw. You might stop breathing, or have difficulty breathing, and could go blue around your mouth.
After a tonic-clonic seizure, you might have a headache and feel sore, tired and very unwell. You might feel confused, or have memory problems. You might go into a deep sleep. When you wake up, minutes or hours later, you might still have a headache, feel sore and have aching muscles.
The symptoms of a tonic seizure are like the first part of a tonic-clonic seizure. But, in a tonic seizure, you don’t go on to have the jerking stage (clonic). You may cry out.
Atonic seizures are also called drop attacks. If you have atonic seizures, you will lose all muscle tone and drop heavily to the floor. These seizures are very brief and you will usually be able to get up again straight away. However, you might hurt your face, nose or head when you fall.
These are usually isolated or short-lasting jerks that can affect some or all of your body. They are usually too short to affect your consciousness. The jerking can be very mild, like a twitch, or it can be very forceful.
Myoclonic seizures often only last for a fraction of a second and you might have a single jerk or clusters of several jerks.
Absence seizures usually develop in children and adolescents. The two most common types of absence seizure are typical and atypical.
If you are having a typical absence seizure, you will be unconscious for a few seconds. You will stop doing whatever you were doing before it started, but will not fall. You might appear to be daydreaming or ‘switching off’ or people around you might not notice your absence. You might blink and have slight jerking movements of your body or limbs. In longer absences, you might have some brief, repeated actions. You won’t know what is happening around you, and can’t be brought out of it.
Some people have hundreds of absences a day. They often have them in clusters, and they are often worse when they are waking up or drifting off to sleep.
These absences are similar to, but not the same as, typical absences. They last longer. You will have less loss of consciousness, and may have a change in muscle tone. You might be able to move around, but you will be clumsy, and need some guidance and support. You may be able to respond to someone during an atypical absence seizure.
People who have atypical absences usually have learning disabilities, other seizure types, or other conditions that affect their brain.
If you would like to see this information with references, visit the Advice and Information references section of our website. If you are unable to access the internet, please contact our Epilepsy Helpline by email at email@example.com
Epilepsy Action wishes to thank Dr John Paul Leach, consultant neurologist, Honorary Clinical Associate Professor, Glasgow, UK for reviewing this information.
This information has been produced under the terms of The Information Standard.
- Updated July 2014To be reviewed July 2017