Epilepsy is a condition in which a person has recurrent seizures or fits caused by disturbances in the brain's electrical activity. These disturbances can last from a few seconds to a few minutes. The part of the brain affected by the disturbance determines the type of seizure.
There are two main types of seizure – partial (or focal) and generalised. Partial seizures occur when the disturbance is located in one part of the brain, while generalised seizures affect the whole brain. During a simple partial seizure, an individual remains conscious but may experience stiffening or jerking of a limb, or a change in emotions, taste or smell.
A generalised seizure may cause loss of consciousness and convulsions, although some individuals, particularly children, can have brief generalised seizures without convulsions that are called 'absence' seizures. In some situations a partial seizure may progress to a generalised seizure.
Seizures may be linked to head injury, stroke, infection or other identifiable problems, but in many cases of epilepsy, there is no known cause.
Usually seizures can be controlled with antiepileptic medications. When taken regularly, these medications stop seizures or reduce their frequency and severity. For many people with epilepsy, medication completely controls seizures.