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).
Seizure - tonic-clonic; Seizure - grand mal; Grand mal seizure; Seizure - generalized
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
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.
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
Review Date:
3/28/2009
Reviewed 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.