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What are seizures?

Seizures are the signs or symptoms that result from abnormal electrical activity in the brain. They come in many different forms, ranging from mild to severe, with varying symptoms depending on the location and the extent of electrical irregularities in the brain.


Warning signs of seizures have been reported to involve feelings of anxiety or déjà vu, a metallic taste in the mouth, nausea, dizziness, flushing, changes in sensation, focal limb jerking or changes in vision such as seeing flashing or bright lights, spots or lines.

Seizures occur suddenly and can include:

  • Brief loss of consciousness
  • Behavioral changes
  • Sudden changes in mood
  • Drooling
  • Frothing at the mouth
  • Unusual eye movements
  • Shaking
  • Convulsions
  • Sudden falling
  • Clenched teeth
  • Loss of bladder or bowel control
  • Impaired breathing

When to see a doctor

Prolonged seizures lasting more than five minutes may require immediate medical attention. They may be a sign of a serious underlying neurological issue and can cause injury, pose safety risks and have negative effects on mental and physical wellbeing. Seek out a medical professional if you think you or a loved one is suffering the symptoms of a seizure.


Some causes of seizures include:

  • Rapid metabolic changes, including low level glucose levels
  • Sudden, high rise in body temperature
  • Birth defect
  • Family history of seizure
  • Brain injury
  • Alcoholism
  • Illicit drug use
  • Brain tumor
  • Stroke
  • Encephalitis or other brain infections
  • Drug withdrawal
  • Sleep deprivation

How is it diagnosed?

If your doctor suspects that you’ve had a seizure, the focus will be on determining an underlying medical condition that may have triggered it. This may include reviewing your medical history and eyewitness reports. Diagnosis may also include a thorough medical and neurological examination with a variety of tests, such as:

  • Blood tests
  • Computerized tomography (CT) scan
  • Magnetic resonance imaging (MRI)
  • Drug screen
  • Spinal tap (lumbar puncture)
  • Brain CT or MRI
  • Electroencephalogram (EEG)

Types of seizures

  • Atonic seizures, also called drop attacks or drop seizures, cause muscles to suddenly lose tone and strength. They can either be slight such as drooping eyelids, a nodding of the head, or an unclenching of the hand, or more intense in cases where brief paralysis occurs or causes the person to fall. The seizures may place the person experiencing them at a high risk for injury during a lapse, and secondary harm can be an issue.
  • Tonic seizures involve brief stiffening of the body, typically where the person will lose consciousness. When their muscles rapidly tense, this may cause them to fall from a sitting or standing position. This is sometimes accompanied by a brief vocalization such as a moan or a scream, the result of air quickly being released from the lungs. As the person recovers they may be confused with an absence of memory of the event, as well as experiencing physical and nervous exhaustion.
  • Tonic-clonic seizures, formerly known as grand mal seizures, can affect both children and adults and are convulsive. A single episode can occur or will repeat over time and become chronic. Epilepsy is the most common cause of tonic-clonic seizures. As its name suggests, there are two phases of a tonic-clonic seizure. The first and shortest phase, or tonic seizure, causes a violent contraction of muscles accompanied by a loss of consciousness. The jaw also becomes clenched which may result in the tongue being bitten. The person may appear to be blue and because of air forced past the vocal chords, the patient may let out cries or moans. This phase usually will not last longer than a minute. In the next phase, or clonic seizure, an intense jerking of muscles will begin, contracting and relaxing, until the spasms gradually subside at which time the person sighs then resumes a regular breathing pattern. This phase rarely lasts longer than a few minutes and is often followed by a period of confusion and exhaustion.
  • Myoclonic seizures are brief, involuntary contractions of muscles or groups of muscles lasting less than one second. An episode can be isolated, or occur repeatedly within a short amount of time. Myoclonic seizures may cause irregular movements that affect both sides of the body, which can inhibit one’s ability to eat, talk or walk. Treatment involves antiepileptic medications.
  • Generalized seizures may be primary or secondarily generalized seizures. A primary generalized seizure is when abnormal electrical activity is widespread, rapidly affecting both sides of the brain at once. This typically will result in loss of consciousness and/or full body shaking or stiffening, though different types of generalized seizures also exist. Secondarily generalized seizures occur when abnormal electrical activity in one side of the brain (a partial seizure) later spreads to both sides of the brain. A generalized seizure usually lasts for a few minutes in duration.
  • Focal, or partial, seizures are caused by abnormal electrical activity which begin in one portion of the brain, but may spread to other areas during an episode. Some focal seizures may not affect memory or awareness. Other focal seizures do involve enough brain tissue to affect memory and awareness, as well as behavior, before, during and immediately following the episode. In over 30 percent of cases, secondary generalization occurs, which is when the partial seizures expand into seizures that affect the whole brain and cause loss of consciousness and convulsive activity.

Types of treatment

If you’ve been diagnosed with seizures, you’ll be prescribed an anti-seizure medication. Your doctor will start with a low dosage and adjust this based upon what is needed to control your seizures. Additional treatment may include surgery, vagus nerve stimulation implant, or lifestyle changes which include:

  • Avoiding alcohol and caffeine
  • Getting plenty of rest
  • Ketogenic diet

Other instructions

When witnessing a seizure, the best thing to do is to remove any objects nearby that pose a risk for injury and monitor the individual’s breathing and pulse. Never forcibly restrain an individual who is having a convulsion as that can increase risk of injury. Similarly never place any object or fingers into the mouth of a person having a seizure, as there is a risk of injury, breaking a tooth or breathing a foreign object into the lung. Instead, place a soft cushion or rolled garment under the head to protect against injury during the convulsion.

Our Epilepsy Center offers comprehensive inpatient and outpatient epilepsy services designed to improve the lives of patients and their families dealing with epilepsy and related disorders.

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