What is the quantitative sudomotor axon reflex test (QSART)?
The QSART is a test that measures the autonomic nerves that control sweating. The test is useful in assessing autonomic nervous system disorders, peripheral neuropathies, and some types of pain disorders. The test requires a mild electrical stimulation on the skin called iontophoresis, which allows acetylcholine, a naturally occurring chemical, to stimulate sweat glands. The QSART measures the volume of sweat produced by this stimulation.