Safety evaluations are done periodically and include vital sign measurements, physical examination, blood and urine tests, review of drug side effects, electrocardiogram (ECG), Holder monitor (2 hour ECG), and QSART (NIH only). The QSART (quantitative sudomotor axon reflex test) measures the amount of sweat in a particular area of skin, mostly the forearm. For this test, a cup partly filled with a liquid is strapped on the arm. A weak electric current is turned on, stimulating the sweat glands, and the amount of sweat produced is measured. There is a tingling sensation when the current is turned on.