The brain controls how the body moves by sending out small electrical signals through the nerves to the muscles. Seizures, or convulsions, occur when abnormal signals from the brain change the way the body functions.
Seizures are different from person to person. Some people have only slight shaking of a hand and do not lose consciousness. Other people may become unconscious and have violent shaking of the entire body.
Shaking of the body, either mild or violent, does not always occur with seizures. Some people who have seizures have symptoms before the seizure (auras) or briefly lose touch with their surroundings and appear to stare into space. Although the person is awake, he or she does not respond normally. Afterwards, the person does not remember the episode.
Not all body shaking is caused by seizures. Many medical conditions can cause a type of body shaking that usually affects the hands and head (tremors).
A small number of people will have only one seizure during their lifetime. A single seizure usually lasts less than 3 minutes and is not followed by a second seizure. Any normally healthy person can have a single seizure under certain conditions. For instance, a sharp blow to the head may cause a seizure. Having one seizure does not always mean that a serious health problem exists. But if you have a first-time seizure, you should be checked by your doctor. It is important to rule out a serious illness that may have caused the seizure. Fever seizures (febrile convulsions) are the most common cause of a single seizure, especially in children. For more information, see the topic Fever Seizures.
Causes of seizures
A seizure can be a symptom of another health problem, such as:
- A rapidly increasing fever (fever seizure).
- An extremely low blood sugar level in a person who has diabetes.
- Damage to the brain from a stroke, brain surgery, or a head injury.
- Problems that have been present since birth (congenital problems).
- Withdrawal from alcohol, prescription medicine, or illegal drugs.
- An infection, such as meningitis or encephalitis.
- A brain tumour or structural defect in the brain, such as an aneurysm.
- Parasitic infections, such as tapeworm or toxoplasmosis.
Eclampsia is pregnancy-related seizure activity that is related to high blood pressure. It is a life-threatening condition for both a mother and her baby (fetus) because during a seizure, the fetus's oxygen supply is drastically reduced. Eclampsia is more likely to occur after the 20th week of pregnancy. For more information, see the topic Preeclampsia and High Blood Pressure During Pregnancy.
Non-epileptic seizure (NES) is a condition that can cause seizure-like activity without having a central nervous system problem. NES can be related to a mental health problem. The physical symptoms may be caused by emotional conflicts or stress. The symptoms usually appear suddenly and at times of extreme emotional stress.
Protect a person during a seizure
No matter what caused the seizure, you can help the person having a seizure.
A person who has had a seizure should not drive, swim, climb ladders, or operate machinery until he or she has seen a doctor about the seizure.
Treatment of a seizure depends on what has caused the seizure.
Check your symptoms to decide if and when you should see a doctor.
Health Tools help you make wise health decisions or take action to improve your health.
Check Your Symptoms
The medical assessment of symptoms is based on the body parts you have.
- If you are transgender or non-binary, choose the sex that matches the body parts (such as ovaries, testes, prostate, breasts, penis, or vagina) you now have in the area where you are having symptoms.
- If your symptoms aren’t related to those organs, you can choose the gender you identify with.
- If you have some organs of both sexes, you may need to go through this triage tool twice (once as "male" and once as "female"). This will make sure that the tool asks the right questions for you.
Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
- Your age. Babies and older adults tend to get sicker quicker.
- Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
- Medicines you take. Certain medicines, such as blood thinners (anticoagulants), medicines that suppress the immune system like steroids or chemotherapy, or natural health products can cause symptoms or make them worse.
- Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
- Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.
Try Home Treatment
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
- Try home treatment to relieve the symptoms.
- Call your doctor if symptoms get worse or you have any concerns (for example, if symptoms are not getting better as you would expect). You may need care sooner.
Neurological symptoms—which may be signs of a problem with the nervous system—can affect many body functions. Symptoms may include:
- Numbness, weakness, or lack of movement in your face, arm, or leg, especially on only one side of your body.
- Trouble seeing in one or both eyes.
- Trouble speaking.
- Confusion or trouble understanding simple statements.
- Problems with balance or coordination (for example, falling down or dropping things).
Symptoms of serious illness may include:
- A severe headache.
- A stiff neck.
- Mental changes, such as feeling confused or much less alert.
- Extreme fatigue (to the point where it's hard for you to function).
- Shaking chills.
Symptoms of serious illness in a baby may include the following:
- The baby is limp and floppy like a rag doll.
- The baby doesn't respond at all to being held, touched, or talked to.
- The baby is hard to wake up.
Make an Appointment
Based on your answers, the problem may not improve without medical care.
- Make an appointment to see your doctor in the next 1 to 2 weeks.
- If appropriate, try home treatment while you are waiting for the appointment.
- If symptoms get worse or you have any concerns, call your doctor. You may need care sooner.
Call 911 Now
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.
Seek Care Now
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
- Call your doctor now to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don't have one, seek care in the next hour.
- You do not need to call an ambulance unless:
- You cannot travel safely either by driving yourself or by having someone else drive you.
- You are in an area where heavy traffic or other problems may slow you down.
Seek Care Today
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
- Call your doctor today to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don't have one, seek care today.
- If it is evening, watch the symptoms and seek care in the morning.
- If the symptoms get worse, seek care sooner.
If you witness a seizure, your account of the seizure will help a doctor diagnose and treat the person. Try to stay calm. Pay close attention to what happens during and after the seizure.
During a seizure:
- Protect the person from injury.
- Keep him or her from falling if you can, or try to guide the person gently to the floor.
- Try to move furniture or other objects that might injure the person during the seizure.
- If the person is having a seizure and is on the ground when you arrive, try to position the person on his or her side so that fluid can leak out of the mouth. But be careful not to apply too much pressure to the body.
- Do not force anything, including your fingers, into the person's mouth. Putting something in the person's mouth may cause injuries to him or her, such as chipped teeth or a fractured jaw. You could also get bitten.
- Do not try to hold down or move the person. This can cause injury, such as a dislocated shoulder.
- Pay close attention to what the person is doing so that you can describe the seizure to rescue personnel or doctors.
- How the person's body moved
- How long the seizure lasted
- How the person acted before the seizure
- How the person acted immediately after the seizure
- Whether the person suffered any injuries from the seizure
- Protect the person from injury.
After a seizure:
- Check the person for injuries.
- If you could not turn the person onto his or her side during the seizure, do so when the seizure ends and the person is more relaxed.
- If the person is having trouble breathing, use your finger to gently clear his or her mouth of any vomit or saliva.
- Loosen tight clothing around the person's neck and waist.
- Provide a safe area where the person can rest.
- Do not give anything to eat or drink until the person is fully awake and alert.
- Stay with the person until he or she is awake and familiar with the surroundings. Most people will be sleepy or confused after a seizure.
A person who has had a seizure should not drive, swim, climb ladders, or operate machinery until he or she has seen a doctor about the seizure and the doctor has said that the person is allowed to drive or operate machinery.
Symptoms to watch for during home treatment
Call your doctor if any of the following occur during home treatment:
- The pattern of your seizures changes and you have a history of epilepsy.
- Symptoms become more severe or frequent.
Note: If you think you may have a seizure disorder or are being evaluated for one, do not drive, operate heavy machinery, swim, climb ladders, or participate in other potentially dangerous activities until you have been specifically cleared to do these things by your doctor.
- Wear your seat belt when you are in a motor vehicle. Use child car seats.
- Do not use alcohol or other drugs before or during sports (such as soccer, football, horseback riding, or bicycling) or when operating an automobile or other equipment.
- Wear a helmet and other protective clothing whenever you are bicycling, motorcycling, skating, kayaking, horseback riding, skiing, snowboarding, or rock climbing.
- Wear a hard hat if you work in an industrial or construction area.
- Do not dive into shallow or unfamiliar water.
- Prevent falls at home by removing hazards that might cause a fall.
If you are being treated for a seizure disorder:
- Be sure to follow your treatment plan. Taking too little or too much of your medicine, abruptly stopping your medicine, or changing your medicine schedule can cause seizures.
- Do not drive, operate heavy machinery, swim, climb ladders, or participate in other potentially dangerous activities until you have been specifically cleared to do these things by your doctor.
- Avoid activities that might trigger a seizure, such as playing video games that have flashing or flickering lights. In rare cases, the flashing lights and geometric patterns of video games can trigger seizures in children.
Preparing For Your Appointment
To prepare for your appointment, see the topic Making the Most of Your Appointment.
You can help your doctor diagnose and treat your condition by being prepared to answer the following questions:
- How was your health and behaviour before the seizure?
- Did you have any unusual symptoms before the seizure (aura)?
- What happened during the seizure? Ask the person who witnessed your seizure to either record this information for you or come to your doctor's appointment with you.
- What kind of body movement occurred?
- How long did the seizure last?
- How did you act immediately after the seizure?
- Are there any injuries from the seizure?
- Have you ever had a seizure before? If so, what was the diagnosis and how were the seizures treated?
- If you have epilepsy:
- What seizure medicines have been prescribed?
- Has the dosage of your seizure medicine changed recently?
- Have you taken your seizure medicine exactly as prescribed?
- Have you taken other prescription or non-prescription medicines or consumed alcohol recently?
- Have you used any alternative medicine products recently?
- When was your last seizure?
- On the average, how often do you have a seizure?
- Have you had other health problems in the past 3 months?
- Have you ever had a concussion (traumatic brain injury) in the past?
- How long ago?
- How severe was it?
- Did you lose consciousness?
- What tests were used to evaluate your head injury?
- Have you had problems with headaches?
- Have you recently taken, stopped taking, or changed the dose of any medicines, including non-prescription medicines or illegal drugs?
- Have you suddenly reduced or stopped drinking alcohol?
- Have you recently travelled to a rural area or an undeveloped country?
- Do you have any health risks that may increase the seriousness of your symptoms?
If possible, ask the person who witnessed your seizure to come to your doctor's appointment with you. Be sure to ask your doctor what you can do to prevent another seizure and what to do if you have another seizure.
Current as of:
July 1, 2021
Author: Healthwise Staff
William H. Blahd Jr. MD, FACEP - Emergency Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
H. Michael O'Connor MD - Emergency Medicine
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