Autonomic Nerve Function Test (ANS /AFT)

What is Autonomic Nerve Function Test (ANS /AFT)?

The autonomic nervous system regulates automatic body functions, such as heart rate, blood pressure, respiration rate and perspiration. ANS /AFT helps to measure these functions.

Your doctor may recommend this test to:

• Investigate dizziness, fainting, blood pressure fluctuations
• Evaluate neurological conditions

This list is non-exhaustive.

How should I prepare for ANS /AFT?

Before the day of test

• Not required to fast
• Continue with your regular diet and medications (unless instructed differently by your doctor)
• If you have an implanted electronic device, such as a heart pacemaker, defibrillator, intracranial device, or neurostimulator, please contact your appointed neurodiagnostic laboratory before your appointment.

On the day of test

• Do not apply body lotion on your arms and legs
• Wear loose shirts, blouses, bermuda shorts or shorts
• Bring a copy (online or hardcopy) of the medications (name and dosages) you are taking. Pass this information to the neuro technologist before your test.

How is ANS /AFT performed?

The test is performed by a neurotechnologist and takes approximately 30 minutes. It includes the following, and not all may be performed, depending on your condition:

• Electrodes patches (sticky pads) will be placed on your palms and soles to record the potential of the skin on sweating, after an electrical stimulation.
• Electrodes patches (sticky pads) will be placed on your chest to record your heart rhythm while you: 
  • follow breathing exercises; and
  • get up from a lying position to a standing position.
• Once the tests are done, all electrodes will be removed, and you can go home. 
• A detailed report will be sent to your doctor within the next two weeks. Your doctor will discuss the findings with you at your next appointment.

Frequently asked questions about ANS /AFT

Is the test safe?

Yes, the test is: 

• Non-invasive (no needles)
• A neurotechnologist will be present throughout the process. If you feel unwell, please inform the neurotechnologist.

Can I use Medisave to pay for this test?

This test may be claimable under:

• Flexi-MediSave for Seniors; or
• Outpatient scans for diagnosis or treatment of a medical condition.

Please refer to the Ministry of Health's Outpatient Care page for the latest claim limits and eligibility criteria.

The information is correct as of July 2026 and subject to revisions without notice.
Content adapted from NNI Neurodiagnostic Laboratory (NDL), NNI@TTSH.