ACTION AND USES: Cardiac tonic of digitalis group; unreliable as to rate of absorption. DOSAGE: 0.75 Gm. or 12 grains (N.F.). _Fluidextractum Apocyni (Fldext. Apocyn.), Fluidextract of Apocynum, N.F._ (Fluidextract of Canadian Hemp).--Apocynum (100%). Absolute alcohol content about 50 per cent. DOSAGE: 0.75 Cc. or 12 minims (N.F.). =*Apomorphinae Hydrochloridum (Apomorph. Hydrochl.), Apomorphine Hydrochloride, U.S.P.= (Apomorphine Chloride). White powder, becoming greenish on exposure to light and air, odorless and with a slightly bitter taste. Soluble in water (1:50) and in alcohol (1:50). ACTION AND USES: Prompt, centrally acting emetic, especially adapted for hypodermic administration. Rarely used as nauseant expectorant. DOSAGE: Expectorant 0.003 Gm. or 1/20 grain (U.S.P.). Probably too large; 0.004 Gm. or 1/15 grain is said to have produced death in a person enfeebled by chronic bronchitis. From 0.001 Gm. to 0.002 Gm., or 1/60 to 1/30 grain, repeated once an hour or once in two hours, is safer. Emetic, by mouth (hypodermic administration is better), 0.01 Gm. or 1/6 grain (U.S.P.). Emetic, hypodermic, 0.005 Gm. or 1/12 grain (U.S.P.). This may be repeated at ten-minute intervals until effective, but it should be remembered that in some cases apomorphin produces toxic effects without causing vomiting. =*Aqua (Aqua), Water, U.S.P.=--H{2}O. ACTION AND USES: Solvent. The ingestion of large amounts is a very valuable eliminative measure. _*Aqua Destillata (Aq. Dest.), Distilled Water, U.S.P._--Water obtained by distillation. _Aqua Destillata Sterilisata (Aq. Dest. Steril.), Sterilized Distilled Water, U.S.P._--Should be used within forty-eight hours after its preparation. =AQUAE AROMATICAE, AROMATIC WATERS.=--The official aromatic waters are aqueous solutions of volatile substances, usually volatile oils. They are used as vehicles for the more active water-soluble drugs. For preparations included in this list see under the names of the principal constituents. For the following, see under the names of the respective oils: Aqua Amygdalae Amarae, Aqua Foeniculi, Aqua Menthae Piperitae and Aqua Menthae Viridis. =Aralia (Aralia), Aralia, N.F.= (American Spikenard, Spignet).--Rhizome and roots. ACTION AND USES: Obsolete irritant, diaphoretic and "alterative." Probably without value. DOSAGE: 2 Gm. or 30 grains (N.F.). _Fluidextractum Araliae (Fldext. Aral.), Fluidextract of Aralia, N.F._--Aralia (100%). Absolute alcohol content about 55 per cent. DOSAGE: 2 Cc. or 30 minims (N.F.). =*Argenti Nitras (Arg. Nit.), Silver Nitrate, U.S.P.=--AgNO{3}. Colorless plates, darkening on exposure to light in the presence of organic matter; odorless; strongly caustic and having a bitter, metallic taste. Very soluble in water (1:0.4) and soluble in alcohol (1:30). Incompatible especially with chlorides and organic matter.