About seizures

Electrical activity is happening in the brain all the time. A seizure happens when there is a sudden burst of intense electrical activity in the brain. This intense electrical activity causes a temporary disruption to the way the brain normally works. It mixes up the brain’s messages, which causes an epileptic seizure.

In these web pages, the term ‘epileptic activity’ is used to talk about this intense electrical activity.

Seizures can happen in any part of the brain. The brain is responsible for all the workings of our mind and body. So what happens to your child during a seizure depends on where in the brain the seizure is happening.

Seizure classifications

There are many different types of seizure. They can be classed by where in the brain the epileptic activity starts.  The International League Against Epilepsy, a world-wide organisation of epilepsy professionals, has compiled a list of the names of different seizure types. The names given to different types of seizures on these web pages are based on this list.

Giving seizures the right names is important for doctors, because specific drugs and treatments can help some seizure types but not others.

Focal (partial) Seizures

In these seizures, the epileptic activity starts in just a part of a child’s brain. They may stay alert during this type of seizure, or they may not be aware of what is happening. They may have unusual sensations or feelings. These are some examples.

• Flushing, sweating, going very pale, having a churning feeling in their stomach
• Seeing things as smaller or bigger than they really are
• Seeing or hearing something that is not actually happening
• Smelling non-existent smells
• Tasting non-existent tastes
• Feeling frightened, panicky, sad or happy
• Feeling detached from what is going on around them
• Feeling sick
• Having movements they can’t control
• Chewing, smacking their lips, swallowing or scratching their head
• Fumbling with their buttons or taking their clothes off
• Having problems speaking or understanding
• Wandering off, without any awareness of what they are doing, or where they are going

Focal seizures can be very brief or last for minutes. Sometimes, focal seizures can turn into generalised seizures.

Generalised seizures

These seizures involve epileptic activity in both hemispheres (halves) of a child’s brain. They will usually lose consciousness but this may be so brief that no-one notices. Their muscles may stiffen and/or jerk. They may fall down.

Tonic-clonic seizures

This is the most common and widely recognised generalised seizure. There are two phases to this type of seizure: the ‘tonic’ phase, followed by the ‘clonic’ phase.

The tonic phase

The child loses consciousness and, if standing, will fall to the floor. Their body goes stiff because all their muscles contract. They may cry out because their muscles contract, forcing air out of their lungs. Their breathing patterns change, so there is less oxygen than normal in their lungs. Because of this, the blood circulating in their body is less red than usual. This causes their skin (particularly around their mouth and under their finger nails) to appear blue in colour (called ‘cyanosis’). They may bite their tongue and the inside of their cheeks.

The clonic phase

After the tonic phase has passed, the clonic phase of the seizure begins. The child’s limbs jerk now because their muscles tighten and relax in turn. They may occasionally lose control of their bladder and/or bowels. It is not possible to stop the seizure, and you should not try to control their movements, as this could cause injury to their limbs.

Absence seizures

During an absence seizure, a child is very briefly unconscious. They appear to be daydreaming or switching off. They don’t know what is happening around them, and they can’t be brought out of it. Because anybody can daydream at any time, absences can be very hard to spot. Some children have hundreds of absence seizures a day, stopping them from fully taking part in daily activities. They could also miss out on tiny pieces of information or events. This may be mistaken for lack of attention or concentration.

Myoclonic seizures

The word myoclonic comes from ‘myo’ meaning muscle, and ‘clonus’ meaning jerk. So, if a child has a myoclonic seizure, their muscles jerk. These seizures can sometimes cause their whole body to jerk. More usually, they only cause jerking in one or both of the child’s arms and sometimes their head. Although it may not be obvious, during the seizure, they are unconscious for a very brief time. Even though the seizures are brief, they can be extremely frustrating. For example, if a child is holding a drink when they have a myoclonic seizure, they are likely to spill it.

Tonic seizures

In a tonic seizure all the child’s muscles tighten. Their body stiffens and they fall over unless they are supported. Tonic seizures usually last less than 20 seconds and most often happen during sleep.

Atonic seizures (drop attacks or akinetic seizures)

In an atonic seizure a child loses all muscle tone and drops heavily to the floor. The seizure is very brief and they are usually able to get up again straight away. They are not confused afterwards. Because they usually fall forward in an atonic seizure, they are at risk of banging their head on furniture or other hard objects. If your child has frequent atonic seizures, extra safety precautions – like protective headgear – make sense. Epilepsy Action can provide further information on this.

Febrile seizures

Febrile seizures happen to around three out of every hundred children under the age of five. They are usually linked to a childhood illness such as tonsillitis, or teething. Febrile seizures are not epilepsy. However, children who have had febrile seizures have a slightly higher chance of developing epilepsy later on than children in general.

Seizures at different ages

Seizures in babies can be difficult to recognise. This is because their brains are immature, and can’t produce the body movements seen in older children. Seizures in newborn babies may show as changes in breathing patterns or movements of their eyelids or lips. They may have bicycling movements of their legs, brief jerks, or episodes of stiffening of their body and limbs.

Some babies and children can have several different types of seizures.