Skip to Content



An electroencephalogram (EEG) measures the electrical activity in your brain. An EEG can help caregivers diagnose brain conditions such as seizures and brain tumors.


The week before your procedure:

  • Write down the correct date, time, and location of your procedure.
  • Ask your caregiver if you need to stop using aspirin or any other prescribed or over-the-counter medicine before your procedure or surgery.
  • Bring your medicine bottles or a list of your medicines when you see your caregiver. Tell your caregiver if you are allergic to any medicine. Tell your caregiver if you use any herbs, food supplements, or over-the-counter medicine.
  • Arrange a ride home. Ask a family member or friend to drive you home after your surgery or procedure. Do not drive yourself home.

The night before your procedure:

  • Wash your hair. Do not use hairspray, oil, or conditioners on your scalp or head.
  • Ask your caregiver if you need to be sleep-deprived for your EEG. Sleep-deprived means you sleep less than you usually do the night before your procedure. This is done so that you are able to sleep during the EEG.

The day of your procedure:

  • Do not drink or eat any caffeine the morning of the procedure. Caffeine may change the result of your EEG.
  • Eat a regular meal before the EEG. This will keep your blood sugar from dropping too low. Low blood sugar can change the result of your EEG.
  • Ask your caregiver before taking any medicine on the day of your procedure. These medicines include insulin, diabetic pills, high blood pressure pills, or heart pills. Bring a list of all the medicines you take, or your pill bottles, with you to the hospital.
  • You or a close family member will be asked to sign a legal document called a consent form. It gives caregivers permission to do the procedure or surgery. It also explains the problems that may happen, and your choices. Make sure all your questions are answered before you sign this form.
  • Your caregiver may give you medicine if he wants you to sleep during the EEG.


What will happen:

  • Your EEG will be done in a room that is dark and quiet. You will either lie in a bed or sit in a reclining chair during the procedure. A caregiver will clean 20 to 21 areas of your scalp. Then, a gel or cream will be placed on these areas. Electrodes (sensors) will be placed on the gel or cream. The electrodes will be connected with wires to a machine or computer. An electrode may also be put on each earlobe.
  • Lie very still with your eyes closed. Try to relax. Do not talk during the test. The EEG machine or computer will record your brain waves. During the EEG, you may need to breathe deeply and quickly for 3 to 4 minutes. You may be asked to look into a bright flashing light. You may be videotaped during the EEG.

After your procedure:

The electrodes and wires will be removed. A caregiver will remove the cream or gel from your scalp and hair. Most EEGs are done in 90 minutes or less. Your caregiver may talk to you about the EEG results before you leave. Your caregiver may send a letter to you explaining the EEG results within 7 days.


  • You cannot make it to your EEG appointment on time.
  • You have questions or concerns about your EEG.

Seek Care Immediately if

Your symptoms are worse.


The flashing light or fast breathing may cause a seizure during the EEG. Trained caregivers will be there to help you. If you do not have this procedure, caregivers may not be able to treat your illness.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.