Seizures are caused by an abnormal focus of electrical activity within the brain. The causes of seizures are quite varied and include:
- a tumour or blood in the brain
- scarring within the brain from surgery or radiotherapy
- high fevers
- dehydration
- some medications or drug withdrawal
- head trauma
There are many different types of seizures with a range of signs and symptoms. In general, seizures may be divided into 2 types:
- Focal seizures are due to an abnormal electrical impulse that is confined to a small area of the brain. Focal seizures can produce abnormal sensations, such as numbness or tingling; involuntary movement of a limb or twitching in the face; or transient inability to speak. The symptoms experienced by the person having the seizure relate to the location within the brain of the abnormal impulse. Therefore, a focal seizure tends to be experienced in the same way each time a person has one.
- Generalized seizures occur when the abnormal impulse is transmitted across a larger area of the brain. Consciousness is affected, and there may be convulsions and/or loss of bowel and bladder control. Often there is little or no memory of the seizure once it ends.
Seizures tend to last only 30 to 60 seconds. Focal seizures may evolve into generalized seizures.
Vocational implications
Seizures are managed with antiepileptic drugs that reduce the frequency and severity of seizures, but may not eliminate them completely. Many people affected by seizures continue to work. There may be some restrictions on work activities. For example, there are legal implications regarding driving for those who have had a seizure or who stop taking seizure medications. Special precautions may need to be in place if patients operate heavy machinery, climb ladders, work on rooftops, cycle, scuba dive or perform other activities that could be dangerous if they have a seizure.
See also this information about driving restrictions.
What patients can do
Tell your patient whether they are at risk for seizures and, if so, how they can be prevented (see below). If the patient has had a seizure, consider recommending seizure medication. Even patients who take seizure medication may still be at risk for seizures, and sometimes people need to be on more than one seizure medication.
Precautions to prevent seizures:
- Inform the healthcare team if taking any new medications. Drug interactions are common and can make seizure medications less effective.
- Avoid physiologic stress, e.g., from dehydration or skipped meals.
- Avoid intense temperatures, e.g., saunas.
- Get enough rest and good sleep, as being overtired can provoke seizures.
- Avoid serious injury in case a seizure occurs. For example, wear a helmet when cycling; swim or hike with a buddy, not alone; take showers, not baths.
- Teach family members and work colleagues what to do when they observe a seizure.
- Read the First Aid for Seizures pamphlet (PDF) from Epilepsy Ontario.
- Know the signs of seizure medication toxicity, including slurred speech, visual changes, nausea and imbalance. Seek medical attention if experiencing any of these problems, as the medication dose may need to be changed.
Job accommodations
There are several ways that jobs can be modified to accommodate seizures:
Modify work tasks:
- Identify situations at high risk for injury (e.g., working at heights or with heavy equipment).
- Request alternative tasks that reduce injury risk to the employee and others in case of a seizure.
- Reduce injury risk with safety equipment when possible (e.g., harnesses).
- If the patient works alone or in an isolated area, consider an auto-alert lifeline that will contact emergency services in case of a fall.
- Identify any seizure triggers and eliminate or reduce them (e.g., high level of stress, over-fatigue, flickering lights).
Modify work schedules:
- Avoid fluctuating shifts.
- Ask for a shift change to prevent over-fatigue (e.g., day shifts only).
Modify the work environment:
- Tell the supervisor or the workplace occupational health advisor what steps to take if the patient has a seizure.
- If the patient is comfortable disclosing the possibility of seizures to co-workers, tell them what to do if the patient has a seizure.
It is not unusual for people who have seizures to have changes in their memory. See cognitive challenges for tips on dealing with these concerns.
To know: Driving restrictions related to seizures vary provincially and should be reviewed within your home province.