DIAPHORETICS (from 8cay6opmo, to carry through), such remedies as promote perspiration. In health there is constantly taking place an exhalation of watery vapour from the skin, by which not only are many of the effete products of nutrition eliminated, but the body is kept cool. Under exertion or in a heated atmosphere this natural function of the skin is increased, sweating more or less profuse follows, and, evaporation going on rapidly over the whole surface, little or no rise in the temperature of the body takes place. In many forms of disease, such as fevers and inflammatory affections, the action of the skin is arrested, and the surface of the body feels harsh and dry, while the temperature is greatly elevated. The occurrence of perspiration not 'infrequently marks a crisis in such diseases, and is in general regarded as a favourable event. In some chronic diseases, such as diabetes and some cases of Bright's disease, the absence of perspiration is a marked feature; while, on the other hand, in many wasting diseases, such as phthisis, the action of the skin is increased, and copious exhausting sweating occurs. Many means can be used to induce perspiration, among the best known being baths, either in the form of hot vapour or hot water baths, or in that part of the process of time Turkish bath which consists in exposing the body to a dry and hot atmosphere. Such measures, particularly if followed by the drinking of hot liquids and the wrapping of the body in warm clothing, seldom fail to excite copious perspiration. Numerous medicinal substances have a similar effect, although the modus operandi appears to differ in the case of several of them. Thus antimony and ipecacuan appear to produce their diaphore.tic action by their nauseating and depressing or relaxing effects ; while others seem to act as direct stimulants to the function of the sudoriparous glands of the skin, such as the well-known diaphoretics - Mindererus spirit (acetate of ammonia), guaiacum, nitrous ether, and the recently intro-duced drug, jaborandi. Opium acts powerfully as a, diaphoretic, especially when in combination with ipecacuan, as in Dover's powder, or with antimony ; and alcohol has similar properties. Diaphoretics are of great service in many diseases. When employed at the commencement of a catarrh or common cold they frequently check- it, and thus prevent the evils which are so apt to follow this affec-tion. In acute dropsy due to kidney disease, such as that which sometimes results from scarlet fever, the hot air or hot water bath is a valuable remedy, and even in dropsical accumulations of long standing, when diaphoresis can be induced, marked improvement in the symptoms generally follows. In certain circumstances, however, diaphoretics, particularly in the form of baths, may be unsafe, especially where there is any affection of the heart or lungs attended with embarrassed respiration ; and in general in diseases where diaphoretics seem to be indicated, the physician is required to take into account the patient's whole condition in his selection of any one remedy for this purpose.