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 present itself in different ways depending on the area of the brain that is affected.

Persons who have lived with epilepsy for much of their lives may find that their seizures change as they get older. 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.


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.

Simple Partial Seizures

In a simple partial seizure, the person may have 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 are known as an aura.  An aura can occur alone, or can be followed by a generalized seizure.

Complex Partial Seizures

In a complex partial seizure, the person loses awareness and appears dazed and confused. The person shows odd 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 abnormal electrical activity in the brain occurs in the entire brain. The two most common forms are generalized absence seizures and tonic-clonic seizures.

Absence Seizures

During an absence seizure, the person appears to be staring into space and his/her eyes may roll upwards. This seizure lasts 5 to 15 seconds and the person is unaware. When the seizure has ended, the person will not remember what happened. Absence seizures most often occur in childhood and disappear by adolescence. They are less frequent in adulthood.

Tonic-Clonic Seizures

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 will jerk and twitch (convulse). Bladder control may be lost. The person loses consciousness during the seizure.


Status Epilepticus

Status Epilepticus is a 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 five 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 rare occurence is unknown, and most often strikes those with uncontrollable seizures who have experienced seizures for more than a year. While 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.


Non-Epileptic Seizures

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. 

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.