Mustard seed contains black mustard glucoside, glucoside itself no stimulation effect, but the water under the effect of myrosinase generated after volatile oil, the main ingredients for isothiocyanate allyl acetate, pungent and spicy stimulation. Applied to the skin, have a warm feeling and make it red, or even cause blisters, pustules. Will usually made mustard mustard powder after the removal of fat oil used plaster, as an irritant (stimulant drugs used in local skin, its role is not limited to medicine, and other parts involved and treatment effect, known as resistance stimulation), treatment of neuralgia, rheumatism, pleurisy and sprains, etc. Wet with lukewarm water before use, to strengthen the role of myrosinase (boiling water to inhibit the action of the myrosinase). Application time not more than 15 to 30 minutes, the skin is sensitive person can only be applied for 5-10 minutes. Mustard powder used as a flavoring, increase of saliva and amylase after sex, reduce the volume of heart and the heart rate. A small amount can stimulate the gastric mucosa increased gastric and pancreatic juice secretion, sometimes can relieve intractable hiccups. Internal and can quickly cause vomiting in great quantities, can be used for the treatment of narcotic drug poisoning.