Seizures occur because the brain becomes irritated and an "electrical storm" occurs. This "electrical storm" affects the normal connections between brain cells, causing abnormal brain function. The electrical surge may affect most of the brain causing it to shut down (generalized seizure), or it may affect only small parts of the brain (focal seizure). In a generalized seizure, in which much of the brain is involved, muscle shaking occurs because the brain is sending out signals to every muscle group, directing them to contract. Most seizures are self-limiting and are followed by a so-called postictal period, when the brain can take time to "reboot and restart" all its programs, similar to a computer when it is rebooted.
Seizures are a common event, and 4% of people will experience at least one in their lifetime. The potential to have a seizure depends upon the threshold of the brain to withstand excess electrical activity. In infants and children, high fevers can cause this threshold to lower, resulting in febrile seizures. A blow to the head can cause an electrical spike causing a post-traumatic seizure, and sometimes seizures just happen.
The patient needs a medical evaluation to look for the reason for the seizure. Is there an infection? Are there electrolyte abnormalities in the blood? Is there a structural problem in the brain? Often there is no obvious reason why the first seizure occurred, and CT or MRI scans of the brain as well as an electroencephalogram (EEG) may be ordered to look for a cause.
Most people get a "freebie" seizure before requiring medication (medication is not necessarily prescribed for every person who has had an isolated seizure), but that doesn't mean that the event should be ignored. The chance of having another seizure sometime in the future is approximately 20%, and that is the reason why it is required that people need to be seizure-free for 3 to 6 months before being allowed to drive a vehicle (the required time varies between states), scuba dive, sky dive, or participate in other potentially risky situations in which a seizure could put the individual or others in danger. These behaviors also include swimming and taking a bath when alone.
Generalized seizures are frightening to witness. There is loss of consciousness; the body stiffens, arches, and may shake. Grunting sounds may be heard. But most seizures stop themselves and the role of the Good Samaritan, bystander, friend, or family is to protect the affected individual from harming him- or herself.
Steps to take if you witness an individual having a seizure include:
- The first step is to take a deep breath and try to stay calm.
- Make certain that there is nothing nearby that can be struck by the person having the seizure.
- Don't hold the person down. A seizure is a violent and forceful event, and bystander injury is a possibility.
- Do not put anything in the victim's mouth. It is a myth that a person who is seizing may swallow their tongue. Usually, the victim can breathe adequately. Forcing open the jaw is dangerous and the helper can break teeth or get fingers bitten.
- If the individual's seizure lasts more than 3 to 5 minutes, call 9-1-1 immediately.
- After the seizure stops, lay the person on their side in the rescue position and stay with them until they are awake or until medical assistance arrives.
Tintinalli J., et al. Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 7th edition. McGraw-Hill Professional, 2010.