Counterirritant mustard

Black mustard is a light olive-brown powder obtained by grinding the dried ripe seeds of several varieties of plants of the Brassica genus moisture yields from this, through enzymatic hydrolysis of a contained glycoside, are about 0.6% of the volatile oil of mustard, which has as its main ingredient the irritant compound allyl isothiocyanate. Mustard is available in bulk and as the official plaster, the latter used only for the local irritant (counterirritant) properties it develops when applied to the skin after moistening with tepid water. 

The Sinapis genus contains several different types of mustard species, including Sinapis alba (white mustard) and Sinapis arvensis (charlock mustard). Mustard has traditionally been used in heated compresses (sinapisms) to draw blood away from underlying infections and to act as a counterirritant. This can cause direct skin damage. 

THERAP CAT Emetic counterirritant. theRAP Cat (vet) See Mustard, Black. 

Hazardous Decomp. Prods. Heated to decomp, or on contact with acid or acid fumes, emits highly toxic fumes of CN, SOx, and NOx Uses Fumigant ointments mustard plasters synthetic flavoring agent in foods and pharmaceuticals counterirritant in external analgesic prods. 

Counterirritation by the application of mustard poultices or moxas was also widely recommended. By 1884, however, Mackenzie was able to declare that bleeding or even the local abstraction of blood was of little value, and that he himself had found counterirritation to be of no effect. He favored derivatives and especially recommended the use of extremely hot... 

Volatile mustard oil (or allyl isothiocyanate) is an extremely powerful irritant and produces blisters on the skin. It is also tear producing (lachrymatory) and has counterirritant properties when greatly diluted (e.g., 1 in 50). It should not be tasted or inhaled when undiluted. It is one of the most toxic essential oils (gosselin jiangsu martindale). ... 

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