Seizures are sudden bursts of abnormal electrical activity in the brain that may affect a person's muscle control, movement, speech, vision, or awareness (consciousness). The effects of seizures depend on a person's individual response, as well as the seizure type, frequency, and severity.

Some seizures make a person fall to the ground in convulsions, in which the muscles stiffen or jerk out of control. Others may stare in a trancelike state, have only a few muscle twitches, or sense a strange smell or visual disturbance not experienced by anyone else.

Sometimes a seizure is a symptom of another medical problem, such as a high fever (especially in children), a stroke, infection, low blood sugar (hypoglycemia), very low blood pressure, or a brain tumor.

By	Healthwise Staff
Primary Medical Reviewer	William M. Green, MD - Emergency Medicine
Primary Medical Reviewer	Adam Husney, MD - Family Medicine
Specialist Medical Reviewer	H. Michael O'Connor, MD - Emergency Medicine
Specialist Medical Reviewer	Steven L. Schneider, MD - Family Medicine
Last Revised	October 12, 2009