ACETANILIDE, also called antifebrin, made by the inter action of glacial acetic acid (q.v.) with aniline (q.v.). It is a febrifuge or antipyretic, used in headaches and fevers, of which it reduces the pain without removing the cause. The dose is 0.1 to 0.3 grams (II to 5 grains). It is liable to cause aniline poison ing, a depressant action on the heart muscle, resulting in collapse, nausea, vomiting and a blueness of lips and nails. The last is caused by certain chemical changes in the blood, whereby red cor puscles lose their power to carry oxygen. Acetanilide is a white, crystalline substance melting at 115° C, boiling at 305° C and soluble in water, alcohol or ether. Its chemical formula is