Complex seizure

Alternative names
Seizure - complex; Partial complex seizure


A partial complex seizure is a brief and temporary alteration in brain function. It is caused by abnormal electrical activity in a specific, discrete area of the brain. The seizure is characterized by a change in alertness or awareness, behavioral or emotional symptoms, and temporary loss of memory. See also temporal lobe seizure.

Causes, incidence, and risk factors

Partial complex seizures may occur at any age, as a single episode or as a repeated, chronic condition (seizure disorder, epilepsy). They are uncommon in very young children.

During the normal functioning of the brain, information is transmitted from nerve cell to nerve cell by an electrochemical process. This process can be detected as electrical activity by an electroencephalograph (EEG). Abnormal patterns of electrical activity are associated with seizures.

Given sufficient circumstances, any person will have a seizure. Partial complex seizures are usually the result of abnormal electrical activity in the temporal lobes of the brain. The most common cause is when a specific area of the brain has been damaged by lack of oxygen, trauma, brain tumors, or discrete brain lesions of any sort.

In tissue studies, about 47% of children with partial complex seizures were found to have hippocampal sclerosis (hardening in the area of the brain called the hippocampus).


  • alteration in consciousness  
  • confusion, disorientation  
  • decreased awareness/alertness  
  • lack of concentration  
  • loss of judgment  
  • difficulty talking  
  • delirium (rare)  
  • eye or head deviation to one side  
  • automatisms (complex, purposeless movements such as picking at clothing)       o abnormal behaviors       o may appear drowsy or intoxicated       o normal activities (such as eating or driving) may continue automatically  
  • sensory hallucinations       o smell, impaired (somewhat common)       o abnormal taste (somewhat common)       o visual hallucinations       o auditory (hearing) hallucinations  
  • recalled emotion (somewhat common)  
  • sense of unreality  
  • sense of deja vu  
  • abdominal pain or discomfort  
  • nausea  
  • sweating  
  • flushed face  
  • dilated pupils (eyes)  
  • rapid heart rate/pulse  
  • chest pain  
  • difficulty breathing, absent breathing  
  • changes in vision, speech, thinking, awareness, personality  
  • complex hallucinations or illusions  
  • a loss of memory (amnesia) regarding events surrounding the seizure (very common)  
  • may be confused for a short period of time after the seizure

Note: Symptoms commonly persist for longer than 15 seconds. Typically they last no longer than 2 minutes.

Signs and tests
The diagnosis is based primarily on the symptoms of the patient. The diagnosis of the cause begins with a completephysical examination, including a detailed neuromuscular examination, blood tests, and a possible lumbar puncture to rule out infection of the central nervous system.

  • An EEG may show changes characteristic of partial seizures, and may show the focus (the location of the cause) in the temporal or frontal lobe of the brain. A normal EEG does not rule out the possibility of seizures.  
  • A head CT or head MRI scan may show the location and extent of the lesion causing the symptoms.

You should write down details of the seizure so you can report them to the health care provider. Include the date and time of the seizure, how long it lasted, which body parts were affected, the type of movements or other symptoms, possible causes, and other factors noted.

Emergency treatment may not be required unless the seizure becomes generalized or consciousness is lost - call an emerency number (such as 911) if you have any questions. First-aid measures should be performed as appropriate, including protecting the patient from injury during the seizure, preventing the patient from inhaling vomit or mucus into the lungs, protecting the patient’s airway, or assistance with breathing.

Complex partial status epilepticus is a condition in which partial complex seizures recur frequently in minutes. It is characterized by changes in mental status, decreased alertness, confusion, decreased responsiveness, and automatic behaviors. It may be very difficult to diagnose and may require and EEG to confirm.

Diazepam (Valium) given intravenously is the primary treatment for status epilepticus of any type. Other medications may be given (as with the status epilepticus of a generalized tonic-clonic seizure).

Treatment of the causes may stop the seizures from recurring in the future. This may include medication, surgical repair of tumors or brain lesions, or other treatments.

An isolated seizure with an obvious avoidable trigger (such as fever or toxic reactions) is treated by removing or treating the precipitating factor.

An isolated seizure without an obvious cause (examination and EEG are normal, and no abnormalities appear on other testing) may not require treatment.

Oral anticonvulsants (anti-seizure medications) may prevent or reduce the number of future seizures. Response varies, and medication and dosage may have to be adjusted repeatedly.

An isolated seizure with abnormal findings on an EEG or other tests is treated with anticonvulsant medications such as phenytoin, carbamazepine, phenobarbital, or valproic acid. Multiple, repeated seizures are often treated with phenytoin or carbamazepine for long-term, preventive use. Other medications include levetiracetam, oxcarbazepine, gabapentin, lamotrigine, topiramate, and Gabitril.

During followup appointments, the physician would probably want to review the need for drugs at least yearly. Drugs may need to be continued indefinitely. Plasma drug-level monitoring is important for continued control of seizures and keeping side effects to a minimum.

Pregnancy, lack of sleep, skipping doses of medications, use of drugs and medications or alcohol, or illness may cause seizures in a person with a previously well controlled seizure disorder.

The patient may be advised to wear informational jewelry or cards (such as Medic-Alert) to help ensure prompt medical treatment if a seizure occurs.

Expectations (prognosis)

Seizures can occur as a single isolated incident, at closely repeated intervals (recurrent multiple seizures), or at various intervals (episodic, paroxysmal). Seizures that recur with little or no observable cause are most commonly associated with seizure disorders (epilepsy). This is a chronic, lifelong condition.

Seizures that occur singly or in a closely associated group are commonly caused by an acute condition such as brain injury. They may occur as an isolated incident, or they may develop into a chronic seizure disorder. Seizures within the first two weeks of a brain injury do not necessarily mean that a chronic seizure disorder will develop.

A seizure-free period may mean that medications may be reduced or eliminated. Medications should be changed only under the supervision of the health care provider.

Death or permanent brain damage from seizures is rare, but either can occur if the seizure is prolonged or many seizures occur soon after each other.

Serious injury can occur if the seizure happens while the person is driving or operating dangerous equipment. These activities may be restricted for people with poorly controlled seizure disorders. Infrequent seizures may not severely restrict lifestyle. Work, school, and recreation do not necessarily need to be restricted.


  • aspiration pneumonia  
  • complications of surgery  
  • injury caused by seizure during driving/operating machinery  
  • injury from falls, bumps, biting self  
  • injury to others  
  • performance of crimes or antisocial acts during seizure  
  • permanent brain damage (stroke or other damage)  
  • progression to generalized seizures  
  • prolonged seizures, closely occurring seizures (status epilepticus)  
  • psychosis (can develop in some individuals)  
  • recurrent seizures (epilepsy)  
  • side effects of medications (with or without observable symptoms)  
  • women choosing to become pregnant should alert their doctor in order to adjust medications prior to pregnancy as many of the anti-epileptic medications cause birth defects

Calling your health care provider
Go to the emergency room or call the local emergency number (such as 911) if the seizure lasts longer than usual for the person. In addition, repeated seizures are an emergency situation if consciousness or normal behavior is NOT regained between them. (This is called status epilepticus.)

Call your health care provider if this is the first time the person has had seizures, if this is a new type of seizure for the person, or if any new symptoms occur, including possible side effects of medications:

  • changes in mental status (drowsiness, restlessness, confusion, sedation, or others)  
  • nausea/vomiting  
  • rash  
  • loss of hair  
  • tremors or abnormal movements  
  • problems with coordination

Treatment of any underlying disorders may reduce the risk of developing seizures. In many cases, however, the seizures may not be preventable.

Johns Hopkins patient information

Last revised: December 2, 2012
by Arthur A. Poghosian, M.D.

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.