Home About Us About Epilepsy • Types of Seizures • Diagnosing Epilepsy • Treatment  • Drug Therapy • First Aid • Living with Epilepsy • Related Articles • Glossary   Programs & Services Resources & Links Events How Can I Help? Contact Us Site Map About Epilepsy: Types of Seizures TYPES OF SEIZURES There are many different types of seizures. Most are classified within two main categories: partial seizures and generalized seizures. A seizure can appear in different ways depending on the area of the brain that is affected. Partial Seizures Partial seizures occur when the excessive electrical activity in the brain is limited to one area. The two most common forms of partial seizures are simple and complex. In a simple partial seizure, the person may experience a range of strange or unusual sensations, such as sudden jerky movements of one body part, distortions in sight or smell, a sudden sense of fear or anxiety, stomach discomfort, or dizziness. These sensations may also be known as an aura. An aura is a simple partial seizure which can occur alone, or can be followed by a generalized seizure. In a complex partial seizure, the person loses awareness as the seizure begins and appears dazed and confused. The person will exhibit meaningless behaviours such as random walking, mumbling, head turning, or pulling at clothing. These behaviours cannot be recalled by the person after the seizure. Generalized Seizures Generalized seizures occur when the excessive electrical activity in the brain encompasses the entire brain; both hemispheres. The two most common forms are generalized absence seizures and tonic-clonic seizures. During a generalized absence seizure, the person appears to be staring into space and his/her eyes may roll upwards. This kind of seizure is characterized by 5 to 15 second lapses of consciousness and, when it has ended, the person will not recall this lapse of consciousness. Generalized absence seizures most often occur in childhood and disappear by adolescence. They are less prevalent in adulthood. During a tonic-clonic seizure, the person will usually emit a short cry and fall to the floor. (This cry does not indicate pain.) The muscles will stiffen and the body's extremities will jerk and twitch (convulse). Bladder control may be lost. Consciousness is lost and may be regained slowly.   Some medical conditions may cause seizures. These include: febrile seizures (caused by high fever in children), withdrawal seizures, and seizures caused by poisoning, allergic reaction, infection, or an imbalance of body fluids or chemicals (low blood sugar). These are not considered to be forms of epilepsy. Persons who have lived with epilepsy for much of their lives may find that their seizures change as they age. The duration of their seizures may become longer or shorter; the intensity of their seizures may worsen or improve; seizure episodes may occur more or less frequently. Seniors also demonstrate a high rate for newly-diagnosed cases of epilepsy. While there is a 10% chance that a person will experience a seizure at some time during their lifetime, a single seizure is not considered to be epilepsy. Status Epilepticus Status Epilepticus is a prolonged or continuous seizure state and is a life- threatening medical emergency. Status epilepticus can be convulsive (tonic- clonic or myoclonic) or non-convulsive (absence or complex partial). A person in non-convulsive status epilepticus may appear confused or dazed. If seizures last 5 minutes or more, or occur one after another without full recovery between seizures - immediate medical care is required. Call 911! SUDEP - Sudden Unexpected Death in Epilepsy The exact cause of this syndrome is unknown, and yet accounts for 12-15% of sudden deaths among people living with epilepsy. It most often strikes those between 20 and 40 years of age who have experienced seizures for more than a year. While awareness needs to be raised, and additional research about SUDEP is necessary, autopsies reveal that 50% of affected patients had AED blood concentrations either below therapeutic levels or in completely undetectable amounts. It is unknown whether this is a result of poor compliance or metabolic issues. *For information regarding other types of seizures, please refer to the  Resources section. Information provided is not intended to replace any medical advice provided by your physician or neurologist. It is intended to supply general information on epilepsy and seizures. For further medical information or specific diagnostic questions, please refer your concerns to your physician or neurologist. Click here for a printable version of this page