codeia, codeina, codeine

[From Gr. kõdei a a poppy head.] I. Chem.: C18H21NO3 or C17H18(CH3) NO3, methyl morphine. An alkaloid obtained by digesting opium with warm water, precipitating the meconic acid with calcium chloride, and concentrating the filtrate; the hydro chlorates of morphine and codeine crystallize out first, and may be separated by treating their aqueous solution with ammonia, which precipitates the morphine; the liquid is then evaporated, and the codeine is precipitated by caustic potash, and recrystallized from ether; it forms colorle prisms when crystallized from water, which lose their water of crystallization at 120°; the anhydrous alkaloid melts at 150°. Codeine is a tertiary monamine; heated with soda lime it gives off methylamine, NH(CH3, and trimethylamine, N(CH3)3. Codeine di olves in concentrated sulphuric acid without color, if the solution is warmed to 150°C.; a trace of molybdic acid turns it a dirty green color, becoming blue; and a drop of nitric acid turns it a violet-red color. II. Pharm.: Codeine is used as a narcotic and hypnotic, as is morphine, but more rarely. It is usually in cases where morphine intolerable to the constitution, and is said to be le likely to nauseate.