Grand Mal Seizure

What Is It?

A grand mal seizure is a common type of generalized seizure that causes a loss of consciousness as well as motor convulsions. It is also known as a generalized tonic-clonic seizure. Probably the most commonly known type of seizure, this is the type of seizure which is usually depicted in movies and television where an individual falls to the floor and convulses.

As a type of generalized seizure, grand mal seizures involve the entire brain, both hemispheres showing diffuse seizure activity. These types of seizures can occur secondary to many predisposing epilepsy conditions or other diseases that cause seizures. They are not exclusive to any one underlying cause. For example, they can occur after trauma or hemorrhage in the brain, due to infections such as meningitis, due to epilepsy conditions such as temporal lobe epilepsy or cortical dysplasia, due to brain tumors and many other conditions.


What Types of Symptoms Are Typical?

Because a grand mal seizure is a generalized seizure, patients loose consciousness with the seizure. Some patients experience an aura before the seizure as with other seizure types. The seizure itself generally starts with the patient loosing consciousness followed by continuous muscle activity called the "tonic" phase because of the tonic muscle contraction. This generally causes the patient to extend their back and arms. After this tonic phase, a clonic phase follows characterized by rapidly alternating movements or convulsions which generally involve the whole body.

The duration of the phases and the entire seizure can very considerably from only seconds to many minutes. Generally the patient slowly recovers consciousness although they are generally quite confused for a period of time. They typically do not have any memory of the seizure event or anything that occurred during that time.

Some patients may have a period of muscle weakness following a seizure that includes convulsions, termed a Todd's Paralysis. This weakness generally slowly improves back to baseline.

Learn more about epilepsy symptoms.


How Is The Diagnosis Typically Made?

As with any seizure, the diagnosis is made both on a combination of the seizure characteristics as well as a follow-up examination. The evaluation generally includes an electroencephalogram as well as imaging studies such as CT scan or MRI.


What Are Some Common Treatments?

Treatments for seizures, including a grand mal seizure or tonic-clonic seizure, vary but generally consist of some form of anti-seizure medication. Further treatment for the underlying cause of epilepsy varies depending on the disease in question.

Learn more about epilepsy treatment, including antiepileptic drugs and surgery.



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Important Note: This site is not intended to offer medical advice. Every patient is different, and only your personal physician can help to counsel you about what is best for your situation. What we offer is general reference information about various disorders and treatments for your education.

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