Medical Information About Grand Mal Seizures

Grand mal seizures, or tonic-clonic seizures, are seizures that affect the entire brain and body. They generally cause a loss of consciousness, violent muscle contractions and muscle rigidity. They affect people of all ages and may occur only once or repeatedly as part of a chronic condition, such as epilepsy. Treatment is with medication to control the frequency and severity of the seizures.

Stages

• Grand mal seizures occur in two stages: the tonic phase and the clonic phase. During the tonic phase, the person loses consciousness. At the same time, the muscles in the body contract, causing the person to fall to the ground. This phase occurs suddenly and generally lasts for less than 30 seconds. During the clonic phase, the muscles in the body begin to rhythmically contract. These convulsions last for two minutes or less. When they continue longer than two minutes, the risk of complications increases.

Symptoms

• In some people, the first symptom of a grand mal seizure may be an aura. Not everyone experiences an aura, and not all auras are the same, but many include feelings of dread or numbness or sensory disturbances. Some people may cry out when a grand mal seizure begins due to seizing of the vocal cords. During the seizure, loss of bladder or bowel control is common. Headaches, fatigue, unresponsiveness, and confusion may develop following a seizure.

Causes

• Grand mal seizures are caused by abnormal electrical activity in the brain. During a grand mal seizure, the abnormal activity affects the entire brain. The underlying cause of the seizures may be difficult to determine, but traumatic head injuries, brain tumors, brain infections, lack of oxygen, and low blood glucose, calcium, magnesium, or sodium levels may all cause grand mal seizures. Brain damage caused by stroke, certain genetic conditions and blood vessel malformation may also be responsible for seizures in some cases. Prolonged sleep deprivation and drug use are other possible causes. For recurrent seizures with no apparent cause, a diagnosis of epilepsy is usually given.

Diagnosis

• An essential part of obtaining an accurate diagnosis is witness accounts of the seizure. Because people who experience a grand mal seizure lose consciousness, most have no recollection of the events preceding or during the seizure. When a grand mal seizure is suspected, a neurological examination and blood tests will be ordered. An electroencephalogram, or EEG, will be conducted to check for abnormal brain waves and activity, and a magnetic resonance imaging, or MRI, scan will be performed to look for tumors, brain bleeds or other potential causes of the seizure.

Treatment

• Treatment may not begin until a second seizure occurs or until a definitive diagnosis is made. For recurrent seizures and epilepsy, medications are the first line of treatment. Anticonvulsant medications, such as valproic acid, carbamazepine, phenytoin, gabapentin or levetiracetam, may be used alone or in combination with other medications or therapies. Medications used to treat grand mal seizures often cause numerous side effects and must be taken long-term.

  Vagus nerve stimulation and surgery are considerations for people who fail to respond to aggressive medication therapy, but these treatment options are not always beneficial for those suffering from grand mal seizures.