Generalized tonic-clonic seizure

Definition

A generalized tonic-clonic seizure is a seizure involving the entire body. It is also called a grand mal seizure. Such seizures usually involve muscle rigidity, violent muscle contractions, and loss of consciousness.

Generalized tonic-clonic 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 part of a repeated, chronic condition (epilepsy).

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Symptoms

Many patients have an aura (a sensory warning sign) before the seizure. This can include vision, taste, smell, or sensory changes, hallucinations, or dizziness.

The seizure itself involves:

Loss of consciousness or fainting, usually lasting between 30 seconds and 5 minutes
General muscle contraction and rigidity (tonic posture), usually lasting 15 - 20 seconds
Violent rhythmic muscle contraction and relaxation (clonic movement), usually lasting for 1 -2 minutes
Biting the cheek or tongue, clenched teeth or jaw
Incontinence (loss of urine or stool control)
Stopped breathing or difficulty breathing during seizure
Blue skin color

Almost all people lose consciousness, and most people have both tonic and clonic muscle activity.

After the seizure, the person usually has:

Normal breathing
Sleepiness that lasts for 1 hour or longer
Loss of memory (amnesia) regarding events surrounding the seizure episode
Headache
Drowsiness
Confusion, temporary and mild
Weakness for up to 24 - 48 hours following seizure (This is called Todd's paralysis.)

References

Foldvary-Schaefer N, Wyllie E. Epilepsy. In: Goetz CG. Textbook of Clinical Neurology. 3rd ed. St. Louis, Mo: WB Saunders; 2007.

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

Krumholz A, Wiebe S, Gronseth G, et al. Practice parameter: evaluating an apparent unprovoked first seizure in adults (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Epilepsy Society. Neurology. 2007;69(21):1996-2007.

Spencer SS. Seizures and epilepsy. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007.

Tomson T, Hiilesmaa V. Epilepsy in pregnancy. BMJ. 2007;335(7623):769-773.

Sheth RD, Hardin CL. Screening for bone health in epilepsy. Epilepsia. 2007;48:39-41

Reviewed on March 28, 2009 by Reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc., and David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine.