EEG (Electroencephalogram)

An EEG (Electroencephalogram) helps analyze brain wave function. Electrodes are placed on the scalp to record the brain’s electrical impulses.


We accept referrals from physicians via email and fax. Physicians may complete the requisition form linked on this page.

Please note: We do not perform sedated EEGs or EEGs for infantile spasms. If your patient is experiencing infantile spasms, they must be referred urgently to the Hospital for Sick Children (Sick Kids).


  • During the EEG, you will lie down on an examining table while electrodes are attached to your head using a fluid and conductive paste.
  • You will be asked to relax and may be asked to breathe deeply and rapidly. A white strobe lamp will flash at a predetermined interval. Both of these activities produce changes in brain-wave patterns.
  • Video will be recorded during the test for better interpretation of brain waves and to correlate brain activity with physical movements.
  • After your test, you may need to wash your hair. The paste used is washable.


  • Discuss any medications you are taking with your doctor.
  • Continue to take any anticonvulsant medications you have been prescribed, unless directed otherwise by your doctor.
  • Wash your hair the night before the test. Do not use hair products (creams, oil, or spray) or makeup.  
  • Refrain from consuming caffeinated drinks or chocolate at least two hours before the test.
  • If possible, please do not bring unaccompanied young children, as full relaxation is desired for this test.

For children:

  • Do not give your child any sedatives (sleeping medication) within 24 hours of the test, unless ordered by a physician.
  • If melatonin has been requested by your referring physician, please take as instructed.
  • Continue all usual medicines, unless instructed otherwise by your physician.
  • Do not give your child any caffeine or sugar within 12 hours of the test.
  • Try to keep your child awake on the way to the clinic.

For sleep-deprived EEG only:

  • Please arrange to have someone drive you to and from your test.
  • Adults: Do not sleep for at least 24 hours prior to the test.
  • Children 4-9: On the night before your appointment, keep your child awake an hour after normal bedtime, and have your child sleep four to five hours less than usual.
  • Children 3 and under: On the night before your appointment, keep your child up an hour past normal bedtime, and wake your child three to four hours before your appointment time.
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