Related article: Rheumatic gout. Headache, giddiness, tinnitus aurium, ophthalmia. Flying blister or sinapism, in pleurisy or pneumonia. Dysmenorrhea, spinal irrita- tion, leucorrhea. > Sciatica. Sciatica. FIG. 36. Diagram of the body showing some of the points where blisters or sinapisms are usually applied. Back view. (Brunton.) Counterirritation is, as a rule, useful only in chronic inflammation. In acute inflammation there is always a danger of increasing the process or of causing it to extend to neighboring organs. 5. To diminish pain, especially in neuralgic and rheumatic affections turpentine and other volatile oils, capsicum, chloroform. 6. As a general tonic, in the form of salt-water baths or alcohol frictions. Therapeutics of Cauterization. Cauterization the destruction of tissue is sometimes employed for severe counterirritation, but particularly to remove tissue: (i) In cases of poisoning, snake-bite, etc.; (2) for the removal of pathologic tissues, tumors, warts, etc. ; (3) indolent granulations, etc.; (4) to cause cicatricial contraction of hypertrophied mucous mem- 122 MANUAL OF PHARMACOLOGY branes (nose, etc.); (5) for removing the nerves of teeth; and (6) to remove superfluous hair. In many cases the chemic cautery has been replaced by galvano- and thermocautery, which are more prompt and permit a more exact limitation of the cauterized area. On the other hand, the slower effect of chemic caustics is of advantage in permitting a graduation in the strength of the action, or in confining it to certain tissue elements. Pathologic formations, being less stable, are in this way more profoundly altered than normal tissue. The caustics may be applied in solid form (sticks, or fused at the end of a probe), in paste, or in solution the first being the most strictly localizable, the last the most dif- fuse. In the latter case, or when the eschar liquefies, the surrounding tissue should be protected by court-plaster. General Toxicology of Irritants. The phenomena produced by irritant poisons depend in the first place upon the part of the body with which they are brought into immediate contact. The most prominent symptoms arise from the skin, alimentary canal, or respiratory organs; the last only in the case of very volatile poisons. Later symptoms may appear in the urinary organs. The extent of the action depends upon the concentration of the poisons, the time during which they act, and the extent of surface with which they come into contact less upon their absolute amount. If taken by the alimentary canal, their action will also be modified by the presence of food. Cauterization of the Skin. This may be accidental or criminal. In the latter case it is usually by sulphuric acid ("Vitriol"). The results are the same as in the case of extensive burns. The diagnosis offers no difficulty. The character of the stains is that described in the next section. Sufficient of the corrosive can generally be collected from the clothing, etc., to establish its identity by chemic means. The treatment is precisely like that for burns, after previous neutralization and removal of the corrosive agent. Salves and oils are useful especially the Linimentum Calcis (Carron Oil, i.e., equal parts Linseed Oil and Lime-water). Caustics in the Eye. These are best washed away by liberal application of water. Caustic Poisoning by the Alimentary Canal. The introduction of caustics by the mouth is generally accidental or suicidal. The effects are so painful, appear so promptly, and the lesions are so persistent, that they would scarcely ever be used in criminal poisoning except possibly in infanticide. They are sometimes taken by mistake for syrup or other medicine, and may be swallowed before the difference is noticed. How- ever, certain organic irritants, usually insoluble, such as croton oil, do not produce their action for some time. The phenomena vary according to whether the irritant produces an actual cauterization a destruction or solution of the tissues; or whether it causes only inflammation. Irritants Which Buy Myambutol Do Not Destroy the Tissue. To this class belong elaterium, croton oil, and most of the other organic irritants, such as volatile oils, formaldehyd, etc. The symptoms are those of a violent gastroenteritis: nausea, vomiting, and diarrhea. If the poison acts only when dissolved, and is insoluble in the stomach, as is croton oil, the nausea and vomiting may not be present, but only the diarrhea. The symptoms will appear correspond- ingly late. The abdomen is usually distended and extremely painful, especially upon pressure. As a result of the gastroenteritis, there is extensive dilatation of the splanchnic area, and consequently withdrawal of blood from other parts of the body. This produces marked changes PHENOMENA COMMON TO LOCAL IRRITANTS 123 in the circulation. The pulse will be soft, small, and quick. The lowered circulation reacts upon other organs, and most conspicuously upon the central nervous system. There is great anxiety, vertigo, delirium, convul-