Bright yellow, odorless, tasteless powder. Almost insoluble in water and wholly insoluble in alcohol or ether. Decomposed by oxidizing agents, alkalies and the haloid salts of the alkali metals (chlorides, bromides or iodides).
Action and Uses: Used principally as an antisyphilitic; generally given in the form of pills. Like all ingestion methods of treating syphilis, much less reliable than the intramuscular administration of mercurials and is falling into disuse on account of relative inefficiency. Has proved of value in lichen ruber planus.
Dosage: 0.01 Gm. or 1/6 grain (U.S.P.).
*Hydrargyri Iodidum Rubrum (Hydrarg. Iod. Rub.), Red Mercuric Iodide, U.S.P. (Biniodide of Mercury, Mercuric Iodide, Red Iodide of Mercury).—HgI2.
Scarlet-red, odorless, nearly tasteless powder. Nearly insoluble in water and slightly soluble in alcohol (1:115); soluble in solutions of soluble iodides, sodium thiosulphate and hot solutions of alkali chlorides.
Action and Uses: Mercuric Iodide, dissolved with potassium or sodium iodide, is used as an antiseptic, germicide and antisyphilitic. It is practically as effective as mercuric chloride and less irritant or corrosive.
Dosage: 0.003 Gm. or 1/20 grain (U.S.P.).
Liquor Hydrargyri et Potassii Iodidi (Liq. Hydrarg. et Pot. Iod.), Solution of Mercury and Potassium Iodide, N.F. (Solution of Potassium Iodohydrargyrate, Channing’s Solution).—Red mercuric iodide (1%), potassium iodide (0.8%), and water.
Dosage: 0.2 Cc. or 3 minims (N.F.).
Hydrargyri Nitras, Mercuric Nitrate.—Hg(NO3)2.