EMETICS, medicines given for the purpose of producing vomiting (q.v.). They are given when it is desirable to relieve the stomach of some noxious or indigestible sub stance, as a narcotic poison, or excess of food, or some special article of diet which has disagreed. E. are also administered in cases of fever, where the copious secretion they produce from the glands of the stomach and intestines is supposed to have a directly curative effect, aided, perhaps, by the sedative action of E. upon the circulation and nervous system. There is a considerable amount of evidence to show, that E. have tne power of cutting short typhus and other fevers in the earliest stage, and afterwards of making the attack of the disease less severe. In diseases of the respiratory organs, E. are given as the quickest and safest method of removing accumulated mucus from the air-passages; and in croup (q.v.), their action is especially favorable, being often
followed by expectoration and a rapid improvement in the suffocative symptoms. E. are to be given with great caution, however, in all very depressed states of the system, as their primary action is to produce nausea (q.v.), which is attended always with more or less diminution of the vital power, and often with great depression of the heart's action, amounting to syncope or fainting. The principal E. are the preparations of antimony, zinc, and copper; ipecacuanha in powder or in wine; squill, lobelia, and, generally speaking, the whole class of expectorants and irritants; the latter of which, however, with the exception of sulphate of zinc, and perhaps mustard and water, form a dangerous kind of E., which should never be administered when the milder kinds can be procured.