MEDICINES AND THEIR CLASSES. 



Alkalies are caustic bases, are soluble in water and 

 alcohol, unite with oils and fats to form soap, neutralize 

 and change reddened litmus paper to blue, &c. Potash, 

 soda, ammonia, lime, and magnesia are the chief alkalies. 



Alkaloids are usually powerful poisons or active med- 

 icines. Those chiefly used are morphine, atrophine, quin- 

 ine, cocaine, pilocarpine, ergotinine, coniine, nicotine, and 

 sparteine. Alkaloids are salifiable bases, that is, they are 

 capable of combining with an acid to form a salt. They 

 are mostly derived from vegetable plants, in which they 

 are usually the active principle. Alkaloid means a kind 

 or form of alkali. 



Alteratives influence the amount and kind of tissue 

 change going on in different organs and cells. Sodium 

 chloride, sulphate, phosphate, acetate, and biborate ; pot- 

 assium nitrate, ammonium chloride and carbonate, and 

 probably all salts excreted by the kidneys, increase tissue 

 change and the quantity of urea excreted. The urea is 

 a component part of the urine. 



Anesthetics (Anaesthetics) diminish and absorb sen- 

 sation. Chloroform, ether, chloral hydrate, nitrous oxide, 

 chloride of olefiant gas, light coal-tar naphtha, &c. Used 

 locally (that is, for certain spots) — cocaine, carbolic acid, 

 and iodoform. 



Anaphrodisiacs diminish sexual passion. Ice or cold 

 water locally ; potassium iodide and bromide ; purgatives, 

 digitalis, and camphor; a spare diet and steady work. 



Anhydrotics check perspiration and skin secretion. 

 Belladonna and atrophine, picotoxine, mix vomica, salts 

 of zinc, &c. 



