Complex partial seizures occur in children and adults with certain forms of epilepsy. They are the most common type of seizure in adults.

• An aura may occur at the beginning of a seizure. It may consist of a strange smell, taste, sound, or visual disturbance, an unexplained feeling of fear or anxiety, or a sense that everything seems strangely familiar, like it has all happened before (déjà vu), or strangely unfamiliar (jamais vu).
• The seizure changes the person's level of consciousness. The person may appear awake but cannot respond to anything or anyone around him or her. The person usually stares into space.
• The seizure may include involuntary movements called automatisms, such as lip-smacking, chewing, hand wringing, picking, and swallowing.
• The seizure lasts 30 seconds to 2 minutes.

Most people who have complex partial seizures do not remember having them. After a seizure, the person will be confused or disoriented and may have a hard time speaking and swallowing for several minutes.

Complex partial seizures are often confused with absence seizures, a type of generalized seizure. Absence seizures, however, never begin with an aura and last only 5 to 15 seconds. Also, a person is fully alert after an absence seizure and may continue with whatever he or she was doing before the seizure as though nothing has happened.