 - Quantitative sudomotor axon reflex test QSART: QSART is a routine clinical test that evaluates the response of the sweat gland to a drug, acetylcholine. One capsule is placed on your forearm and three on your leg and foot. The testing is done by passing a small electrical current, for 5 minutes, to activate the nerves that supply the sweat glands. You will feel a slight burning sensation. 