Quantitative Sudomotor Axon Reflex Test (QSART)

Test Details

Can I eat or drink before the quantitative sudomotor axon reflex test (QSART)?

You can eat a light meal. However:

• Don’t eat or drink anything with caffeine, or smoke four hours before the test.
• Don’t drink anything with alcohol for 12 to 14 hours prior to the test.

What medications can I take before the QSART?

Some medications can interfere with the test. Make sure your provider knows all the medications you’re taking.

• Don’t take any over-the-counter cold or cough medications, aspirin, antihistamines, antidepressants or diuretics 48 hours before the test.

What should I expect during the QSART?

Please come to the test room wearing loose clothing. You’ll be asked to remove your shoes and socks, including compression stockings. The technician will discuss the steps of the test and answer any questions you may have. Then:

• The technician will wipe the skin on your foot, leg and wrist with acetone.
• Four electrodes filled with acetylcholine are then placed on three areas of the leg and one on the wrist.
• The iontophoretic stimulators are turned on, and sweat responses are measured.

The test takes approximately 45 minutes to one hour. A mild burning discomfort may be experienced at the site of stimulation during the test.