Minor test explained

Minor test
Purpose:	for testing sudomotor function

The Minor test (also known as Minor's test, the starch–iodine test, and the iodine–starch test), described by Victor Minor in 1928,^[1] is a qualitative medical test that is used to evaluate sudomotor function (perspiration or sweating).

Method

Tincture of iodine 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.^[2]

When sweat reaches the surface of the skin, the starch and iodine combine, causing a drastic color change (yellow to dark blue), allowing sweat production to be easily seen.^[2]

Some have reported higher sensitivity and fewer drawbacks marking dry skin with water-erasable ink and observing fading.^[3]

Uses

The Minor test can be used as a diagnostic tool to evaluate underactive (hypohidrosis)^[4] and overactive (hyperhidrosis) sweating. This test can also reveal Horner's syndrome.^[2]

Notes

• • (excessive sweating)

Notes and References

1. 10.1007/BF01652699 . Minor . Victor . Ein neues Verfahren zu der klinischen Untersuchung der Schweißabsonderung . 1928 . Deutsche Zeitschrift für Nervenheilkunde . 101 . 302–308 . 9226674 .
2. Sriraam. Laya Manasa. Sundaram. Raja. Ramalingam. Ravi. Ramalingam. K. K.. June 2015. Minor's Test: Objective Demonstration of Horner's Syndrome. Indian Journal of Otolaryngology and Head & Neck Surgery. 67. 2. 190–192. 10.1007/s12070-015-0852-5. 2231-3796. 4460096. 26075177.
3. Hisashi. Uhara. Kenta. Nakamura. Yasutomo. Mikoshiba. Tomomi. Miyake. Ryuhei. Okuyama. Sweat Test with Water-erasable Ink, Letters to the Editor. Acta Dermato-Venereologica . 10.2340/00015555-1300 . Medical Journals/Acta D-V. November 1, 2011. 92 . 4 . 432–433 . 22278410 . https://web.archive.org/web/20220617061110/https://www.medicaljournals.se/acta/content_files/files/pdf/92/4/3633.pdf . 2022-06-17 . live.
4. Chia . K. Y. . Tey . H. L. . 10.1111/jdv.12014 . Approach to hypohidrosis . Journal of the European Academy of Dermatology and Venereology . 799–804 . 2012 . 23094789 . 27 . 7. 206038609 .