What to Expect During an EEG Test — A Complete Patient Guide
Worried about your EEG test? This step-by-step guide covers everything — how to prepare, what happens during the test, and how results are interpreted.
An EEG (electroencephalogram) is one of the most commonly recommended neurological tests — but many patients arrive anxious because they do not know what to expect. The good news: EEG is completely painless, non-invasive, and usually takes 30–45 minutes. At Sri Anand Child and Neuro Center, Chanda Nagar, EEG is performed in-house and interpreted personally by Dr. Anand Karnam — with results discussed on the same day.
How to Prepare for Your EEG Test
Wash Your Hair the Night Before
Come with clean, dry hair. Do not apply any oil, gel, cream, or conditioner on the day of the test — these make it difficult to apply the electrodes properly and affect signal quality. Hair should be completely dry.
Continue Your Regular Medications
Unless specifically told otherwise by Dr. Anand, continue taking all your regular medications as normal before the EEG. Do not stop anti-epileptic drugs before an EEG without explicit instructions — this can be dangerous.
Sleep-Deprived EEG — If Requested
If Dr. Anand has requested a sleep-deprived EEG: sleep only 4–5 hours the night before. This makes it easier to sleep during the test, which can reveal abnormal brain activity not seen in a routine EEG. Arrange for someone to drive you — sleep deprivation impairs driving.
Eat and Drink Normally
There is no fasting requirement for EEG. Eat and drink normally before the test. Low blood sugar can affect results. Have your normal breakfast or meal before coming for the EEG.
Avoid Caffeine Before the Test
Avoid coffee, tea, energy drinks, and cola for 4–6 hours before the EEG. Caffeine can affect brain wave patterns and slightly reduce the sensitivity of the test.
Children — Special Preparation
For children, bring a favourite toy or book to help them stay calm. For infants, try to time the visit so the child is likely to fall asleep during the test (after a feed, when normally due for a nap). Paediatric EEG at Sri Anand CNC is child-friendly.
What Happens During the EEG — Step by Step
Electrode Placement (10–15 Minutes)
You sit in a comfortable chair. A technician measures your head and applies 20–25 small metal discs (electrodes) to specific positions on your scalp using a water-soluble paste. This is not painful. The electrodes measure electrical signals from your brain — they do not deliver any electrical current to you.
Recording Phase (20–30 Minutes)
You relax with your eyes closed. You will be asked to: open and close your eyes several times, breathe fast and deep for 3 minutes (hyperventilation — this can trigger certain abnormalities), and look at a flashing light (photic stimulation). These are activation procedures that increase the sensitivity of the test.
Sleep During the Recording
Sleep during the EEG is beneficial — certain types of abnormal activity are only seen during sleep. You may naturally fall asleep, especially if sleep-deprived. This is fine and expected. The recording continues while you sleep.
Electrode Removal and Cleanup (5 Minutes)
Once recording is complete, the electrodes are gently removed. The paste is wiped off — you may want to wash your hair afterwards as some paste residue may remain. You can drive yourself home unless sleep-deprived.
Same-Day Result Discussion (at Sri Anand CNC)
Dr. Anand Karnam reviews and interprets your EEG recording personally. At Sri Anand CNC, results are discussed with you on the same day as the test — no waiting weeks for a report. You leave knowing what the EEG shows and what it means for your management.
Why Choose Sri Anand Hospital?
Treated by: Dr. Anand Karnam · DrNB (Neurology) · EEG Specialist · 12+ Years
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Sri Anand Child & Neuro Hospital · Open 24/7 · Chanda Nagar, Hyderabad