Minor test
The Minor test, described by Victor Minor in 1928, is a qualitative medical test that is used to evaluate sudomotor function.
Method
is applied to the skin and allowed to air-dry. After drying, the area is dusted with cornstarch or potato flour. Sweating is then encouraged by increased room temperature, exercise, use of a sauna, or pilocarpine.When sweat reaches the surface of the skin, the starch and iodine combine, causing a drastic color change, allowing sweat production to be easily seen.
Some have reported higher sensitivity and fewer drawbacks marking dry skin with water-erasable ink and observing fading.