32 ACTION OF INORGANIC SALTS 



externally. The physiological and therapeutic action of mercury and its 

 salts is extremely varied. Locally they may be entirely inert or they may 

 exert an escharotic influence on the skin. The soluble salts are particu- 

 larly toxic to lower forms of life and form therefore very fine antiseptics. 

 We have mercury salts used as antisyphilitics, as cathartics, as antiseptics, 

 as antiphlogistics, and as diuretics. As an antiphlogistic mercury acts 

 particularly on the so-called endothelial membranes. It has been used for 

 inflammation of mucous surfaces, but is not nearly as beneficial in these 

 conditions. For iritis mercury forms a valuable remedy. Mercury is 

 a specific for syphilis, and although many preparations of arsenic, such as 

 salvarsan and neosalvarsan, the cacodyllates, etc., are used a great deal, 

 mercurial inunctions and injections of the so-called "grey oil" are veiy 

 common in modern clinical practice. 



Mercury may be used as a cathartic and is so used particularly in the 

 form of calomel. Mercury has been used with success as a diuretic, 

 being particularly valuable in chronic parenchymatous nephritis. As 

 an antiseptic mercury is used a great deal in the form of its bichloride. 

 This salt combines with proteins, forming compounds which inhibit re- 

 gular functioning of life processes. 



Forscheimer mentions the following uses for mercury and its salts: 

 syphilis, absorption in pleurisy, tuberculous peritonitis, chancre, gum- 

 mata, acute myelitis, optic neuritis, throat affections, secondary anemias. 



Zinc. Zinc and its salts come under the general head of mineral 

 astringents. The Pharmacopoeia recognizes eleven salts and prepara- 

 tions. Most of the zinc salts are either astringents or antiseptics. The 

 astringent action in -all probability comes from the fact that a typical 

 insoluble salt is formed when coming in contact with protein. 



The oxide is probably more used than any other salt of zinc. It is 

 especially indicated in conditions demanding sedative and astringent action. 

 The stearate of zinc also finds some use along this line. Zinc has been 

 used in epilepsy, although with doubtful success. The sulphate of zinc 

 is a powerful and rapid emetic and is so used at times, especially in cases 

 of poisoning when apomorphine is not available or indicated. Zinc 

 salts are not absorbed from the alimentary tract to any large extent. We 

 do have, however, cases of chronic zinc poisoning. The symptoms here 

 are much like those of lead poisoning, producing colic, and other derange- 

 ments of the alimentary canal. Forschheimer mentions its use in the fol- 

 lowing disorders: chronic laryngitis, oriental sore, bronchopneumonia, 

 stomatitis, vaginitis, gonorrheal urethritis, herpes of lips, gastritis, acute 

 dpium poisoning, nasopharyngitis, peristaltic unrest. 



Antimony. Antimony to-day finds comparatively little use. One 

 salt and one preparation are official in the Pharmacopoeia. In the mid- 

 dle ages about the time of the iatrochemists, we find the virtues of anti- 

 mony lauded to the skies. And we find one of the foremost iatrochemists, 



