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Alternative names Return to top
Seizure - tonic-clonic; Seizure - grand mal; Grand mal seizure; Seizure - generalizedDefinition Return to top
A generalized tonic-clonic seizure is a seizure involving the entire body, usually characterized by muscle rigidity, violent rhythmic muscle contractions, and loss of consciousness. The condition is caused by abnormal electrical activity in the nerve cells of the brain.Causes, incidence, and risk factors Return to top
Generalized tonic-clonic seizures (also called grand mal seizures) are the type of seizure that most people associate with the term "seizure," convulsion, or epilepsy. They may occur in people of any age, as a single episode or as a repeated, chronic condition (epilepsy). The majority of seizures that do occur as just a single episode are generalized tonic-clonic seizures rather than other types.
Generalized seizures are caused by abnormal electrical activity at multiple locations in the brain and/or over a large area of the brain. This results in loss of consciousness and body stiffening, which is followed by shaking of the arms and legs.
Abnormal electrical activity may start in one part of the brain and cause isolated symptoms (see partial seizures). Sometimes this abnormal electrical activity spreads through the brain, resulting in a generalized seizure. Seizures can be caused by a specific area of the brain that is injured or inflamed, or they can be due to stress on the brain from a more widespread systemic process, such as severely low blood sugar.
Some of the more common causes of seizures include:
Risk factors include:
Symptoms Return to top
Many patients have an aura (sensory warning sign) preceding the seizure. This can include a visual, taste, smell, sensory, or other hallucination or dizziness.
The seizure itself involves:Signs and tests Return to top
Diagnosis of a grand mal seizure is based on the symptoms and excluding other medical problems that can look like a seizure (such as heart arrythmia). A neuromuscular examination may or may not reveal neurologic deficits (decreases in brain functions) when the person is not actively having seizures.
An EEG may show characteristic changes and in some cases may show the focus (location of the cause of the seizure). An EEG can be normal in between seizures and a normal EEG does not rule out a seizure disorder.
Tests for the cause may include various blood tests (depending on the suspected cause), including:
Treatment Return to top
If a generalized seizure occurs, give appropriate emergency first aid.
EMERGENCY FIRST-AID TREATMENT
EMERGENCY TREATMENT BY MEDICAL PERSONNEL (status epilepticus)
AFTER THE SEIZURE
Treating the cause, if one has been identified, may stop seizures. This may include medication, surgical repair of tumors or brain lesions, or other treatments. An isolated seizure with an obvious trigger (such as fever and toxic reaction) is treated by eliminating or avoiding the precipitating factor.
An isolated seizure without an obvious trigger (the examination and EEG are normal and there are no abnormalities on other testing) may not require treatment.
Oral anticonvulsants (anti-seizure medications) may prevent or reduce the number of future seizures. The response is individual, and the medication and dosage may have to be adjusted repeatedly. There are numerous medications which may be effective alone or when used in combination. Side effects of these medications and plasma drug-levels will need to be monitored to various degrees, depending on which medications are used.
Women who might get pregnant may need to take additional medications or vitamins to reduce the risk of birth defects associated with some of these medications. Such women may need to be followed in a high-risk pregnancy clinic.
Patients who continue to have seizures despite several medications may benefit from a vagal nerve stimulator (implantable device that stimulates a nerve in the neck) or from brain surgery to remove tissue responsible for causing the seizures.
The use of informational jewelry or cards (such as Medic-Alert or similar products) that indicate a seizure disorder may be advised to help the patient receive prompt medical treatment if a seizure occurs.
Expectations (prognosis) Return to top
Seizures can occur as a single isolated occurrence, as closely repeated seizures, or at various intervals. Seizures that recur create a condition known as epilepsy.
Seizures that occur singly or in a closely associated groups are commonly caused by an condition such as brain injury. They may occur as an isolated incident or may develop into a chronic seizure disorder. Seizures within the first two weeks of a brain injury do not necessarily mean that a chronic seizure disorder will develop.
A seizure-free period may indicate that reduction or elimination of medications may be possible. Medications should be changed only under the supervision of the health care provider.
Death or permanent brain damage from seizures is rare. A serious injury can occur if a seizure occurs while driving or operating dangerous equipment; these activities are often restricted for people with poorly controlled seizure disorders.
Infrequent seizures may not severely restrict the patient's lifestyle. Work, school, and recreation do not necessarily need to be restricted.
Complications Return to top
Calling your health care provider Return to top
Call your local emergency number (911) if this the first time a person has had a seizure or a seizure is occuring in someone without a medical ID bracelet (instructions explaining what to do). In the case of someone who has had seizures before, call the ambulance for any of these emergency situations:
Call your health care provider if any new symptoms occur, including possible side effects of medications (drowsiness, restlessness, confusion, sedation, or others), nausea/vomiting, rash, loss of hair, tremors or abnormal movements, or problems with coordination.
Prevention Return to top
Generally, there is no known prevention for seizures. However, you can decrease the likelihood of triggering a seizure by taking medicines as directed, getting enough sleep, eating a proper diet, and abstaining from alcohol and drugs.
Reduce the chance of head injuries by wearing head protection and avoiding risky behavior.
Update Date: 11/21/2002 Updated by: Joseph V. Campellone, M.D., Division of Neurology, Cooper Hospital/University Medical Center, Camden, NJ. Review provided by VeriMed Healthcare Network.
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Page last updated: 28 October 2004 |