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Seizure

Dr Lynn Thomas, OStJ, BSc, MB.BS, MA, FRCPClinically reviewed: 28/04/2025

Epilepsy is the most common cause of seizures (fits), although there are other causes. Find out what to look for and what to do.

What are seizures and what causes them?

In adults, the most common cause of a seizure, also known as a convulsion or fit, is epilepsy. However, it can be caused by other things, like:

  • lack of sleep

  • stress

  • head injuries

  • alcohol poisoning

  • lack of oxygen

  • after taking certain drugs

  • extreme temperatures

  • flashing lights

  • if someone with diabetes has a 'hypo', where their blood glucose becomes too low.

Epilepsy is a condition that affects the brain and can cause repeated seizures, which often occur suddenly, randomly, and without warning.

Signs and symptoms

Look for:

  • a sudden collapse or loss of responsiveness

  • a rigid body with an arching back

  • noisy, difficult breathing

  • grey-blue tinge on the lips

  • jerky, uncontrolled movements or twitching

  • saliva at the mouth, possibly blood stained if they have accidentally bitten their tongue or lip

  • loss of bladder or bowel control

What to do

  1. 1

    With any seizure, it is important to first protect the casualty from harming themselves during the fit. Ask any bystanders to step back, help to protect the casualty's privacy as much as possible, and clear away any potentially dangerous objects, like hot drinks or sharp objects. Make a note of the time that the seizure started.

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

    • Do not put anything in their mouth.

  2. 2

    Protect their head by placing soft padding underneath it, like a rolled-up towel or pillows. You should also loosen any clothing around their neck.

    You can surround small children with padding for safety. Try to cool them by taking off bedding and strip them of a single layer of clothing, but make sure they don't get cold. You might need to wait for the seizure to stop to do this.

    It can be helpful to capture a video of the seizure on your mobile phone if you can. This can aid diagnosis.

  3. 3

    When any jerky movements have stopped, open their airway and check their breathing.

  4. 4

    Monitor their level of response and make a note of how long the seizure lasted.

    • If they become unresponsive at any time, prepare to call 999 or 112 for emergency help and give CPR.

    Not everyone who has a seizure needs to go to hospital, particularly if they are known to have epilepsy. The casualty may have an alert bracelet or a care plan that says what to do. It may take 15-30 minutes for the casualty to recover completely from a seizure.

  5. 5

    Call 999 or 112 for emergency help if:

    • it is the casualty’s first seizure

    • they are having repeated seizures

    • the cause of the seizure is unknown

    • the seizure continues for more than five minutes

    • the casualty is unresponsive for more than 10 minutes after the seizure

    • they have an injury on another part of the body, or they are not breathing normally

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