380 HALOIDS OR HALOGENS 



Preparations. 



* Unguentum Potassii lodidi. 10 per cent. KI and 0.6 per cent, 

 of Potassium Carbonate. 



Incompatibles. Almost everything: mineral acids, mineral 

 salts, alkaloids, spirits of nitrous ether. 



Action. Potassium iodide is classed as an alterative because 

 no effects will be noticed if a single moderate dose is administered to 

 a healthy animal, except some increase in secretions and possibly some 

 upsetting of the stomach. It is rapidly absorbed from all parts of 

 the digestive tract and reappears in the secretions in a few minutes 

 after its administration to a man. It is chiefly eliminated by the 

 kidneys but small amounts are also eliminated by the saliva, tears, 

 milk and sweat. There is some belief that small amounts are re- 

 tained in the body which may account for its accumulation or iodism. 

 Large doses cause burning in the stomach, and gastroenteritis with its 

 attendant phenomena, while the continuous use leads to a toxic group 

 of symptoms, or iodism. This action has not been satisfactorily ex- 

 plained but by some is believed to be due to the free iodine into which 

 a small amount of the iodide may be changed. The symptoms of iod- 

 ism are especially pronounced in the mucous membranes of the 

 respiratory tract and other mucous membranes involved in its 

 elimination. There is pain in the frontal region, sneezing, run- 

 ning at the nose, soreness of the throat, lachrymation, increased 

 secretion of saliva, loss of appetite and sometimes a scaly skin erup- 

 tion. Some cases may show symptoms of Grave's disease, such as 

 palpitation of the heart, tremors, sweating and loss of weight, prob- 

 ably due to some influence upon iodine in the thyroid gland. In still 

 other cases the prolonged administration of iodine may cause atrophy 

 of the testicles, mammae, paralysis and blindness. Iodism is im- 

 portant to remember because there is a considerable difference in 

 susceptibility of animals to the drug and also for the reason that the 

 drug is frequently pushed to full effect or until iodism occurs and is 

 them immediately stopped. 



Action on Thyroids. Marine and Lenhart found that the thy- 

 roids take up iodine, no matter in what form administered and 

 whether the glands were normal, colloid or hyperplastic. They also 

 found that those with hyperplastic glands lost weight for a week or 

 two after the administration of the iodine but then rapidly gained, 

 and that iodine hastened the tendency of all hyperplasias to become 

 colloid. 



Uses. 1. As a specific in actinomycosis. Administer medium 

 or large doses internally, and apply iodine to the lesion, for sev- 

 eral days, then omit for a few days and begin over again. Or ad- 

 minister the iodide until iodism occurs and then stop it for a time. 



* Unofficial. 



