Grand mal seizures

Tonic-Clonic Seizure, Convulsion, Generalized Convulsive Epilepsy, Major Epilepsy, Myoclonic Epileptic Seizures

What Grand mal seizures it?

Grand mal seizures are caused by abnormal electrical activity of the brain. Normal human activities, thoughts, perceptions, and emotions are produced by electrical impulses that stimulate nerve cells in the brain. During a seizure, the usual electrical communication in the brain is disrupted by a chaotic and unregulated discharge. Seizures are a symptom of brain dysfunction and can be the result of a wide variety of diseases or injuries. Seizures may be associated with birth trauma, head injury, central nervous system infections, brain tumor, stroke, ingestion of toxic substances, or metabolic imbalance.

A grand mal seizure starts with opening of the mouth and eyes. The arms are thrown out and up, and the legs straighten. The respiratory muscles contract, forcing air out of the lungs and creating a sound like a cry or a grunt. The jaws clamp shut and the individual might bite his or her tongue, breathing ceases and the bladder can contract releasing urine. The body collapses and is rigid. The individual loses consciousness. This is called the tonic phase of the seizure and lasts for about 15 to 30 seconds.

The clonic phase immediately follows and is characterized by violent rhythmic muscular contractions of the entire body including the muscles of the face and eyes. The person does not breathe normally as the respiratory muscles are also involved (apnea). The movements gradually subside and the seizure is over in one to two minutes. Breathing becomes regular and the individual falls asleep. Individuals may waken within a few minutes but will be confused, lethargic, and fatigued. This mental state may persist for hours. They often have a headache and don't remember the seizure, or events preceding it. This is called the post-ictal phase.

Seizures that appear to have no apparent cause are called idiopathic seizures. They account for 75% of the cases of grand mal seizures in adults. These seizures may actually be due to microscopic brain lesions that occurred during birth or other trauma, or may be caused by unexplained metabolic disturbances. The term epilepsy is a diagnosis given when an individual has repeated seizure episodes over a period of time.

How is it diagnosed?

History: An important part of the history with a grand mal seizure is to discover if the generalized convulsion episode was preceded by a focal or partial seizure. This type of seizure can be limited to a single part of the body and then "spread" or evolve into a grand mal seizure. This might imply dysfunction in a limited area of the brain that can have a lesion due to birth injury, trauma, tumor, abscess, stroke, abnormal blood vessels (vascular malformation), or some other structural abnormality. Individuals may have a history of seizures, be taking prescribed drugs or "street drugs," or simply have other medical problems such as chronic alcoholism. Chronic alcohol users can have seizures from a myriad of causes. Seizures of any type are simply physical signs of an underlying cause, diagnosed or undiagnosed.

Physical exam: The immediate concern of the physician or emergency personnel who first examine the individual is to make sure the individual's airway is open and unobstructed. If fever is noted, it could be the cause of the seizure or a sign of infection. Any contusions, lacerations, or fractured bones the individual may have sustained during the seizure are noted. A brief neurological examination is performed. A more thorough examination is postponed until the individual is alert and able to follow directions. In the post-ictal phase some neurological findings may be absent or equivocal. The neurological exam is usually focused on finding specific, localized neurological deficits that may indicate areas of brain lesions.

Tests: Blood tests are needed to detect any metabolic abnormalities. A drug screen including a blood alcohol level may be warranted. If the seizure was preceded by fever or a change in mental status, an immediate spinal tap (lumbar puncture) is performed to check the spinal fluid for signs of an infection (meningitis, encephalitis) that might have led to a generalized seizure. Further testing depends on whether or not this was the first time the individual had such as seizure. If it is the first episode without an apparent cause, extensive testing is necessary. Tests can include skull x-rays, MRI, an electroencephalogram (EEG), CT scan, and a cerebral angiogram.

How is Grand mal seizures treated?

When an underlying disease or brain lesion is found to be the cause of the seizure, then the treatment is directed at resolving that problem. If no cause is immediately apparent, the seizures are called idiopathic. Opinion is divided on whether a single seizure incident should receive treatment. Individuals with recurrent seizures are treated with anticonvulsant drugs used alone or in combinations. In almost all cases, these drugs lessen the frequency of seizures.

Depending on the cause of the seizure, and if no seizures occur for two or three years, the medication dose may be reduced or stopped. If medication is ineffective, and the seizures appear to be caused by a single area of brain damage (usually in the temporal lobe), surgery may be considered. Prolonged or repeated seizures (when the individual does not regain consciousness) is a condition called status epilepticus and can be fatal without emergency treatment with intravenous anticonvulsant drugs. Fever, if present is treated.


Tegretol (Carbamazepine), Topamax (Topiramate), Mysoline (Primidone)

What might complicate it?

Status epilepticus is a life threatening condition that is likely to result in brain damage, even with prompt treatment.

Predicted outcome

The outcome of isolated episodes of grand mal seizures that can be attributed to underlying disease or medical conditions depends on the particular diagnosis and treatment. Idiopathic seizures can usually be well controlled or eliminated with drug treatment.


High fevers, meningitis, encephalitis, brain tumors or other brain lesions, alcohol withdrawal, and certain drugs (like cocaine) can cause grand mal seizures.

Appropriate specialists


Last updated 10 May 2016


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