Definition of Rubefacient:
Rubefacients (L. rubere, to be red, + facere, to make) are Irritants or Counter-irritants which produce temporary redness and skin congestion; if left on too long, may cause exudation between the cuticle and true skin (vesicants), or may destroy the tissue, forming a slough (escharotics), or may cause muscular atrophy: mustard, capsicum, mezereum, iodine, menthol, ammonia, arnica, volatile oils (turpentine, cajuput, etc.), hot water, friction [Culbreth1927, pg 46].
Rubefacients are remedies which excite the vessels of the skin and increase its heat and redness [Brown1878; Meyer1932].