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Learn about this type of seizure that can cause convulsions. Also know how to help if you see someone having one.
A tonic-clonic seizure, previously known as a grand mal seizure, causes a loss of consciousness and violent muscle contractions. It's the type of seizure most people picture when they think about seizures.
During a seizure, there's a burst of electrical activity in the brain that causes changes in behavior and movements. Seizures can be focal, meaning the burst of electrical activity happens in one area of the brain. Or seizures can be generalized, in which they result in electrical activity in all areas of the brain. Tonic-clonic seizures may begin as focal seizures in a small area of the brain and spread to become generalized seizures that involve the whole brain.
Focal and generalized seizures have different symptoms. People who have generalized seizures usually lose consciousness. But people who have focal seizures may or may not lose consciousness. In tonic-clonic seizures, the muscles become stiff, causing the person to fall. Then the muscles alternately flex and relax.
Usually, a tonic-clonic seizure is caused by epilepsy. But sometimes this type of seizure can be triggered by other health problems. Very low blood sugar, a high fever or a stroke can cause a tonic-conic seizure.
Many people who have a tonic-clonic seizure never have another one and don't need treatment. But someone who has recurrent seizures may need treatment with daily anti-seizure medicines to control and prevent future tonic-clonic seizures.
Tonic-clonic seizures have two stages:
The following symptoms occur in some but not all people with tonic-clonic seizures:
Call 911 or emergency medical help if:
If you experience a seizure for the first time, see a health care professional.
Also see health care professional if you or your child:
The brain's nerve cells typically communicate by sending electrical and chemical signals across the synapses that connect the cells. Tonic-clonic seizures occur when there's a surge of electrical activity over the surface of the brain. Many nerve cells fire at once, much faster than usual. Exactly what causes the changes to occur often is not known.
However, tonic-clonic seizures are sometimes caused by underlying health problems, such as:
Risk factors for tonic-clonic seizures include:
Having a seizure at certain times can be dangerous for you or others. You might be at risk of:
After a seizure, see a health care professional to thoroughly review your symptoms and medical history. You may need several tests to determine the cause of your seizure. The tests can evaluate how likely it is that you'll have another one.
Tests may include:
An EEG records the electrical activity of your brain via electrodes affixed to your scalp. EEG results show changes in brain activity that may be useful in diagnosing brain conditions, especially epilepsy and other seizure disorders.
Not everyone who has one seizure has another one. Because a seizure can be an isolated incident, you may not start treatment until you've had more than one. Treatment usually involves the use of anti-seizure medicines.
Many medicines are used in the treatment of epilepsy and seizures, including:
Finding the right medicine and dosage can be challenging. A health care professional likely will first prescribe a single drug at a relatively low dosage. The health care professional then may increase the dosage gradually until your seizures are well controlled.
Many people with epilepsy are able to prevent seizures with just one drug. But others need more than one. If you've tried two or more single-drug regimens without success, you may need to try a combination of two drugs.
To achieve the best seizure control possible, take medicines exactly as prescribed. Always call a health care professional before adding other medicines. This includes prescription medicines, medicines available without a prescription or herbal remedies. And never stop taking your medicine without talking to a health care professional.
Mild side effects of anti-seizure medicines can include:
More-troubling side effects need to be brought to the attention of a health care professional immediately. They include:
In rare cases, the medicine lamotrigine has been linked to an increased risk of aseptic meningitis. Aseptic meningitis is an inflammation of the protective membranes that cover the brain and spinal cord. The disease is similar to bacterial meningitis but isn't caused by bacteria.
When anti-seizure medicines aren't effective, other treatments may be an option:
Women who've had previous seizures usually are able to have healthy pregnancies. Birth defects related to certain medicines can sometimes occur.
In particular, valproic acid has been associated with cognitive deficits and neural tube defects, such as spina bifida. The American Academy of Neurology recommends that women avoid using valproic acid during pregnancy because of risks to the baby. It's especially important to avoid valproic acid during the first trimester of pregnancy, if possible.
Discuss these risks with a health care professional. Preconception planning is particularly important for women who've had seizures. In addition to the risk of birth defects, pregnancy can alter medicine levels.
In some cases, it may be appropriate to change the dose of seizure medicine before or during pregnancy. Medicines may be switched in rare cases.
It's also important to know that some anti-seizure medicines can make oral contraceptives — a form of birth control — less effective. Also, some oral contraceptives can speed up the metabolism of seizure medicines. Check with a health care professional to evaluate whether your medicine interacts with your oral contraceptive. Ask if other forms of contraception need to be considered.
In vagus nerve stimulation, an implanted pulse generator and lead wire stimulate the vagus nerve, which leads to stabilization of electrical activity in the brain.
Here are some steps you can take to help with seizure control:
Seizures don't usually result in serious injury. But injury is possible if you have recurrent seizures. These steps can help you avoid injury during a seizure:
It's helpful to know what to do if you witness someone having a seizure. If you're at risk of having seizures in the future, pass this information along to family, friends and co-workers so that they know what to do.
To help someone during a seizure:
It can be stressful to live with a seizure disorder. Stress can affect your mental health, so it's important to talk with a health care professional about your feelings, who can suggest ways you can find help.
Your family can provide much-needed support. Tell them what you know about your seizure disorder. Let them know they can ask you questions, and be open to conversations about their worries. Help them understand your condition by sharing any educational materials or other resources.
Meet with your supervisor and talk about your seizure disorder and how it affects you. Discuss what you need from your supervisor or co-workers if a seizure happens while at work. Consider talking with your co-workers about seizure disorders. This may help you widen your support system. It also may bring about acceptance and understanding.
Remember, you don't have to go it alone. Reach out to family and friends. Ask your health care provider about local support groups or join an online support community. Don't be afraid to ask for help. Having a strong support system is important to living with any medical condition.
Sometimes seizures need immediate medical attention, and there's not always time to prepare for an appointment.
If your seizure wasn't an emergency, make an appointment with a health care professional. You may be referred to a specialist, such as a doctor trained in brain and nervous system conditions, known as a neurologist. Or you may be referred to a neurologist trained in epilepsy, known as an epileptologist.
To prepare for your appointment, consider what you can do to get ready and understand what to expect.
Preparing a list of questions helps make the most of your time at your appointment. For seizures, some basic questions to ask include:
Don't hesitate to ask any other questions that occur to you.
A health care professional is likely to ask you a number of questions, such as: