Seizures: symptoms, causes, first aid and treatment

Seizures vary a great deal from person to person. The NHS says the symptoms of a seizure can include the body becoming stiff or floppy, suddenly falling to the floor, jerking or twitching movements, peeing unintentionally, losing awareness of what is around you (you may stare into space and not respond normally), unusual feelings or sensations such as strange smells, numbness or tingling, changes in vision or suddenly feeling scared, and unusual behaviour such as fidgeting or walking around without being aware of it.

The NHS says a seizure usually lasts a few seconds or minutes and stops by itself, and that you may or may not remember it afterwards. Epilepsy Action says what happens afterwards depends on the type of seizure: some people recover quickly and carry on, while others have a headache, feel sleepy or confused and need time to rest.

Some people get a warning, often called an aura, before the main seizure. Epilepsy Action says this is actually the beginning of a focal seizure, and that not everybody gets one.

Epilepsy Action describes an epileptic seizure as a sudden, intense burst of electrical activity in the brain that scrambles the messages passing between brain and body for a short time. The same charity makes a point that surprises many people: everyone has the potential to have a seizure, but people with epilepsy have a tendency to have repeated ones.

The word covers a wide range. Some seizures involve a fall and shaking. Others are a few seconds of staring, a strange smell, a rising feeling in the stomach or a twitching hand. What happens depends on which part of the brain is involved.

The charity quotes a figure of as many as 4 in 100 people having an epileptic seizure at some point in life. It adds that around half of people who have a single epileptic seizure go on to have at least one more within the next two years.

For epilepsy, the NHS says the normal electrical activity in the brain changes. It is thought to be often related to the genes you inherit from your parents or to changes in your genes, and is sometimes caused by brain damage, for example after a head injury, a stroke or an infection. For many people the cause is not clear; Epilepsy Action puts this at approximately 1 in 2 people with epilepsy.

Seizures can also have causes outside epilepsy. Epilepsy Action lists very low blood sugar, for example in diabetes, an abnormal heart rate or rhythm that causes a convulsive faint, illness or injury, sudden withdrawal from medicines, drugs or alcohol, and pre-eclampsia in pregnancy. Febrile seizures are triggered by a high temperature in young children, and functional (dissociative) seizures happen for other reasons such as stress or traumatic events, not because of abnormal electrical activity.

The NHS suggests keeping a diary to identify things that might trigger a seizure in someone with epilepsy, such as tiredness, stress, periods, flashing lights, food or drink, and says that drinking too much alcohol can increase the risk of seizures.

Epilepsy Action says doctors place epileptic seizures in groups depending on how they affect the brain. Focal seizures start in just one side of the brain, generalised seizures start in or very quickly affect both sides, and where doctors cannot tell, the seizure may be called unknown or unclassified. With generalised seizures you do not usually stay conscious; with focal seizures you may stay conscious and aware, or may not.

Epilepsy Action says it is important to stay with the person until the seizure is over and they are fully recovered, and to look for an epilepsy identity card or identity jewellery, which may give information about their seizures and what to do. The charity also says that first aid differs for each seizure type, so these are general steps only.

For a seizure with jerking, the NHS advice for febrile seizures gives a good outline that applies broadly: check the time the seizure starts and ends, protect the head with your hands or something soft, remove dangerous objects, and after it ends place the person in the recovery position and make sure nothing is in the mouth or throat. Do not move the person or try to hold them in place, and do not put anything in their mouth.

• Note the time the seizure starts, so you know how long it lasts.

• Move dangerous objects away and cushion the head with your hands or something soft.

• Do not restrain the person or move them unless they are in immediate danger.

• Do not put anything in their mouth.

• When the jerking stops, put them in the recovery position and stay until they have recovered.

Epilepsy Action says most people with epilepsy do not need an ambulance when they have a seizure, and some carry emergency medicine; people with epilepsy usually have a care plan that says what to do. The NHS gives clear thresholds for everyone else. Call 999 if it is the first time, if it lasts longer than is usual for the person or longer than 5 minutes if you do not know how long their seizures usually last, if they do not recover as usual or have another seizure without recovering in between, or if they have had 3 or more seizures in 24 hours.

A seizure lasting more than 5 minutes, or one seizure after another without recovery in between, is called status epilepticus. Epilepsy Action calls it a medical emergency and says to call an ambulance immediately, and the NHS says it needs urgent treatment to prevent damage to the brain. If you think you or your child had a first seizure and did not go to hospital, or you have had a seizure after a long time without any, the NHS says to ask for an urgent GP appointment or get help from NHS 111.

Treatment depends on the cause. The NHS says the main treatment for epilepsy is medicine to prevent seizures (anti-epileptic or anti-seizure medicine), and that you may also be given emergency medicine to use if a seizure lasts longer than usual, which a family member or carer will need to give. The medicine recommended depends on the type of seizures and things like age, sex and other conditions, and you may need to try different medicines to find what works.

The NHS says that for most people medicines work well to prevent seizures. Rarely, other treatments are needed: surgery on the brain, a small electrical device under the skin of the chest (vagus nerve stimulation), or a specialist ketogenic diet. If you have not had a seizure for 2 years, your specialist may suggest gradually reducing your dose, but the NHS says not to change your dose or stop your medicine without talking to your specialist.

The NHS also says some epilepsy medicines can harm a baby if taken in pregnancy, so anyone taking them who could become pregnant should discuss treatment with a specialist. Most febrile seizures do not need treatment, but the NHS says a child will be checked in hospital after a first one.

The NHS says anyone who has had a seizure needs to see a specialist doctor. The specialist asks what happened before, during and after, and it helps to bring someone who saw it. Tests may include an electroencephalogram (EEG) of brain activity, an electrocardiogram (ECG) for the heart, an MRI or CT scan, blood tests and genetic testing.

The heart check matters because a faint with jerking can be mistaken for epilepsy. Epilepsy Action lists convulsive syncope among non-epileptic causes. The aim of the work-up is to decide whether this was an epileptic seizure, something else, or a one-off linked to a clear trigger.

For most people the first assessment is through the NHS, usually starting with a GP or emergency department and moving to a neurology or specialist seizure service. Private neurology consultations and scans are sometimes used to shorten waits, but the pathway and tests are the same in principle.

The NHS says a febrile seizure can sometimes happen when a child has a high temperature. They usually last 2 to 3 minutes, are rare beyond 10 minutes, and usually affect children between 6 months and 6 years old. The NHS says a febrile seizure can seem frightening but is unlikely to harm your child or cause long-term effects. Epilepsy Action says around 2 in 100 children under 5 have one.

The NHS says to call 999 or go to A&E if your child has a seizure for the first time, one that lasts more than 5 minutes, difficulty breathing, stiffness and twitching on only one side of the body, is more sleepy than usual for more than an hour afterwards, or has more than one seizure within 24 hours. Do not try to cool the child by undressing them or sponging them with cold water. The NHS says children who have had a febrile seizure have a slightly increased chance of having epilepsy later in life, but this is rare.

GOV.UK says you must tell the DVLA about any epileptic seizure or blackout and stop driving straight away. When you can drive again depends on the type of seizure and how long ago it happened. For a first seizure while awake with loss of consciousness, the page says you may reapply after six months without a seizure if DVLA medical advisers judge the risk low.

The NHS suggests simple safety steps for people with seizures that are not fully controlled. Showers are safer than baths, home hazards can be reduced with carpets and radiator covers, and care is needed around cooking, tools, swimming and sport. A diary of possible triggers such as tiredness, stress, flashing lights, food, drink or periods can help. Heavy drinking can raise seizure risk.