=Acidum Trichloraceticum (Acid. Trichloracet.), Trichloracetic Acid, U.S.P.=--CCl{3}.COOH. Colorless, deliquescent crystals with a slight characteristic odor. Miscible with water and with alcohol. ACTION AND USES: Caustic, for the removal of warts and other skin blemishes. Used also as local hemostatic. =Aconitina (Aconitin.), Aconitine, U.S.P.=--An alkaloid obtained from aconite. A white, odorless powder. Very slightly soluble in water, soluble in alcohol (1:28) and in ether (1:65). ACTION AND USES: Similar to those described under aconite. As several alkaloidal preparations of aconite, of varying activity, are sold under the name of aconitine, its use is not advisable. DOSAGE: 0.15 mg. or 1/400 grain (U.S.P.). _Oleatum Aconitinae (Oleat. Aconitin.), Oleate of Aconitine, N.F._--Aconitine (2%) in oleic acid and olive oil. USES: Without advantage over aconite preparations for external application. =*Aconitum (Aconit.), Aconite, U.S.P.= (Monkshood, Aconite Root, Aconiti Tuber, P.I.).--A tuberous root, yielding about 0.5 per cent. of ether-soluble alkaloids; also assayed biologically. Physicians should specify preparations that have been assayed biologically, since the alkaloidal assay is not a reliable index of activity. ACTION AND USES: Slows the pulse and lowers the blood pressure, but this action in therapeutic doses is uncertain. Used in the treatment of febrile colds; also for counter-irritation, in the form of the tincture. Used also as a local anesthetic, and by some still believed to be useful in the treatment of the symptoms arising from excessive cardiac hypertrophy. Toxic symptoms may occur from local absorption. DOSAGE: 0.03 Gm. or 1/2 grain (U.S.P.); not used as such. _Extractum Aconiti (Ext. Aconit.), Extract of Aconite, U.S.P._ (Powdered Extract of Aconite).--Yields about 2 per cent. of ether-soluble alkaloids. Biologically assayed by producing death in the guinea-pig. DOSAGE: 0.01 Gm. or 1/6 grain (U.S.P.). Physicians who prescribe extract of aconite should specify the biologically assayed product. _Fluidextractum Aconiti (Fldext. Aconit.), Fluidextract of Aconite, U.S.P._--Aconite (100%), yielding about 0.5 per cent. of alkaloids. Absolute alcohol content about 70 per cent. Biologically assayed by producing death in the guinea-pig. DOSAGE: 0.03 Cc. or 1/2 minim (U.S.P.). Physicians who prescribe fluidextract of aconite should specify the biologically assayed product. Best to use the tincture. _Linimentum Aconiti et Chloroformi (Lin. Aconit. et Chlorof.), Liniment of Aconite and Chloroform, N.F._--Fluidextract of aconite (4.5%), in alcohol, chloroform and soap liniment.