Seizures

Definition

A seizure is a sudden change in behavior due to an excessive electrical activity in the brain.

Considerations

There are a wide variety of possible symptoms of seizures, depending on what parts of the brain are affected. Many types of seizures cause loss of consciousness with twitching or shaking of the body. However, some seizures consist of staring spells that can easily go unnoticed. Occasionally, seizures can cause temporary abnormal sensations or visual disturbances.

Seizures can generally be classified as either "simple" (no change in level of consciousness) or "complex" (change in level of consciousness). Seizures may also be classified as generalized (whole body affected) or focal (only one part or side of the body is affected).

Epilepsy is a chronic disorder with recurrent seizures. Some types of epilepsy are hereditary.

See also:

• Epilepsy
• Petit mal seizure
• Generalized tonic-clonic seizure (grand mal)
• Partial (focal) seizure
• Temporal lobe seizure
• Fever convulsions (seizures in children with high fever)

Causes

Any condition that results in abnormal electrical excitation of the brain may result in a seizure, including:

• Epilepsy
• Injury or trauma to the head
• Infection (brain abscess, meningitis)
• Brain tumor
• Stroke

Also, any medical condition that irritates brain cells may result in a seizure. Common medical conditions that commonly cause seizures include:

• Hypoglycemia (low blood sugar)
• Drug use (especially cocaine or stimulants)
• Alcohol withdrawal
• Very high fever (fever convulsions in children)

References

Goetz, CG. Textbook of Clinical Neurology. 2nd ed. St. Louis, MO: WB Saunders; 2003: 1158-1160.

Marx J. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 5th ed. St. Louis, Mo: Mosby; 2002:145-149, 1445.

Hirtz D, Ashwal S, Berg A, et al. Practice parameter: Evaluating a first nonfebrile seizure in children: Report of the Quality Standards Subcommittee of the American Academy of Neurology, the Child Neurology Society, and the American Epilepsy Society. Neurology. 2000;55;616-623.