Used In Medicine Principally In The Form Of:

Tinctura Ferri Chloridi.—Tincture Of Ferric Chloride, U. S. P.

It is a hydro-alcoholic solution of FeCl3, containing not less than 13.28 per cent, of the anhydrous salt, corresponding to about 4.5 per cent, of metallic iron.

Properties : Tincture of ferric chlorid is a bright brownish liquid, having a slightly ethereal odor, a very astringent taste and an acid reaction, miscible in all proportions with either water or alcohol.

Incompatibilities : It is incompatible with alkalies, alkali carbonates and with tannin, and the vegetable astringents. These give an inky color to the mixture. Tincture of ferric chlorid is also incompatible with iodids, from which it liberates iodin.

Action and Uses : Tincture of ferric chlorid is an astringent and is used in applications to the throat. It may be employed as a hematinic. It is also sometimes given in infections like erysipelas, but it is doubtful if it has any special value in this disease.

Dosage: 0.5 c.c. or 8 minims,   freely diluted.     Care should be taken to prevent injury   to the teeth.     Equal parts of the tincture, glycerol and   water form a   useful local application in acute tonsillitis.