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Brain & Nervous System Health Center

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Electromyogram (EMG) and Nerve Conduction Studies

How To Prepare

Tell your doctors all the medicines, vitamins, supplements, and herbal remedies you take.

  • Some medicines can affect the test results. You may need to stop taking some medicines before you have this test.
  • If you take blood thinners, such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin, your doctor will tell you if you should stop taking these medicines before your procedure. Make sure that you understand exactly what your doctor wants you to do.

Wear loose-fitting clothing so your muscles and nerves can be tested. You may be given a hospital gown to wear.

Since the electrodes are attached to your skin, make sure it is clean and free of sprays, oils, creams, and lotions.

You may be asked to sign a consent form that says you understand the risks of the test and agree to have it done.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

How It Is Done

An EMG is done in a hospital, clinic, or doctor's office. It may be done in a room that stops any outside electrical interference. The test may be done by an EMG technologist or a doctor.

You will be asked to lie on a table or bed or sit in a reclining chair so your muscles are relaxed.


The skin over the areas to be tested is cleaned. A needle electrode that is attached by wires to a recording machine is inserted into a muscle.

When the electrodes are in place, the electrical activity in that muscle is recorded while the muscle is at rest. Then the technologist or doctor asks you to tighten (contract) the muscle slowly and steadily. This electrical activity is recorded.

The electrode may be moved a number of times to record the activity in different areas of the muscle or in different muscles.

WebMD Medical Reference from Healthwise

Last Updated: 2/, 014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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