CausesBy Mayo Clinic staff
Often, no underlying cause can be found for absence seizures. Many children appear to have a genetic predisposition to them. Sometimes hyperventilation can trigger an absence seizure.
In general, seizures are caused by abnormal nerve cell (neuron) activity in the brain. The brain's nerve cells normally communicate with each other by sending electrical and chemical signals across the synapses that connect the cells. In people who have seizures, the brain's usual electrical activity is altered. During an absence seizure, these electrical signals repeat themselves over and over in a three-second pattern.
People who have seizures may also have altered levels of neurotransmitters, which are the chemical messengers that help the nerve cells communicate with one another.
This type of seizure may be more prevalent in children. Many children gradually outgrow absence seizures over months to years.
- Absence seizures (also called petit mal). The Epilepsy Foundation. http://www.epilepsyfoundation.org/about/types/types/seizureabsence.cfm?renderforprint=1&. Accessed March 23, 2011.
- FDA: Aseptic meningitis risk with use of seizure drug Lamactil. U.S. Food and Drug Administration. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm222212.htm. Accessed March 23, 2011.
- Hughes JR. Absence seizures: A review of recent reports with new concepts. Epilepsy & Behavior. 2009;15:404.
- Seizures and epilepsy: Hope through research. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/epilepsy/detail_epilepsy.htm?css=print. Accessed March 22, 2011.
- Practice parameter update: Management issues for women with epilepsy - Focus on pregnancy (an evidence-based review): Teratogenesis and perinatal outcomes. Neurology. 2009;73:133.
- Seizure disorders. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/print/sec16/ch214/ch214a.html. March 22, 2011.
- Schachter SC. Evaluation of the first seizure in adults. http://www.uptodate.com/index/home.html. Accessed March 22, 2011.
- Stafstrom CE, et al. Pathophysiology of seizures and epilepsy. http://www.uptodate.com/index/home.html. Accessed March 22, 2011.