A seizure is a sudden, uncontrolled electrical disturbance in the brain. It can cause changes in your behavior, movements or feelings, and in levels of consciousness. If you have two or more seizures or a tendency to have recurrent seizures, you have epilepsy.
There are many types of seizures, which range in severity. Seizure types vary by where and how they begin in the brain. Most seizures last from 30 seconds to two minutes. A seizure that lasts longer than five minutes is a medical emergency.
Seizures are more common than you might think. Seizures can happen after a stroke, a closed head injury, an infection such as meningitis or another illness. Many times, though, the cause of a seizure is unknown.
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, including a head injury, alcohol poisoning, lack of oxygen, after taking certain drugs, or if someone with diabetes has a ‘hypo’ where their blood glucose is too low.
Epilepsy is a condition that affects the brain and can cause repeated seizures, which are often sudden and dramatic.
Signs and symptoms
- sudden loss of responsiveness
- a rigid body with an arching back
- noisy, difficult breathing
- start of jerky uncontrolled movements (uncontrolled)
- saliva at the mouth, possibly blood stained if they have bitten their tongue or lip
Nerve cells (neurons) in the brain create, send and receive electrical impulses, which allow the brain’s nerve cells to communicate. Anything that disrupts these communication pathways can lead to a seizure.
The most common cause of seizures is epilepsy. But not every person who has a seizure has epilepsy.
When to see a doctor
Seek immediate medical help if any of the following occurs:
- The seizure lasts more than five minutes.
- Breathing or consciousness doesn’t return after the seizure stops.
- A second seizure follows immediately.
- You have a high fever.
- You’re experiencing heat exhaustion.
- You’re pregnant.
- You have diabetes.
- You’ve injured yourself during the seizure.
If you experience a seizure for the first time, seek medical advice.