DOSAGE: 0.25 Gm. or 4 grains (U.S.P.). _Elixir Terpini Hydratis (Elix. Terpin. Hyd.), Elixir of Terpin Hydrate, N.F._--Terpin hydrate (1.75%), tincture of sweet orange peel, spirit of bitter almond, alcohol, glycerin, syrup and water. Absolute alcohol content about 42 per cent. DOSAGE: 4 Cc. or 1 fluidrachm (N.F.). _Elixir Terpini Hydratis et Codeinae, N.F._--See under =Codeina=. _Elixir Terpini Hydratis et Diacetylmorphinae, N.F._--See under =Diacetylmorphina=. =Terra Silicea Purificata (Ter. Sil. Purif.), Purified Siliceous Earth, U.S.P.= (Purified Kieselguhr, Purified Infusorial Earth).--Silica (SiO{2}). Fine, bulky, white or nearly white, odorless, tasteless powder. Insoluble in water, acids or dilute solutions of the alkalies. ACTION AND USES: Used as a clarifying agent in pharmacy. =*Theobrominae Sodio-Salicylas (Theobrom. Sodio-Sal.), Theobromine Sodio-Salicylate, U.S.P.= (Diuretin).--Sodium theobromine and sodium salicylate in approximately molecular proportions. Contains not less than 46.5 per cent. of theobromine. White, odorless powder, having a sweetish, saline and somewhat alkaline taste. Freely soluble in water (1:1), slightly soluble in alcohol. Incompatible with acids and has the other incompatibilities of salicylates. ACTION AND USES: A soluble salt of theobromine, having much the same action as caffeine, except that it does not affect the central nervous system to any extent. Mainly used as a diuretic. DOSAGE: 1 Gm. or 15 grains (U.S.P.). =*Theophyllina (Theophyll.), Theophylline, U.S.P.= (Dimethylxanthine, Theocin).--An isomer of theobromine. White, odorless powder, having a bitter taste. Soluble in water (1:100) and in alcohol (1:80). ACTION AND USES: Has a diuretic action similar to that of theobromine, more powerful, but said to be not so lasting. DOSAGE: 0.25 Gm. or 4 grains (U.S.P.). =Thuja (Thuja), Thuja, N.F.= (Arbor Vitae).--Young twigs. ACTION AND USES: Somewhat irritant; no well-defined indications for its use, but has been recommended as a febrifuge, expectorant and anthelmintic, and as a stimulating remedy in tenesmus and dribbling of urine in the aged. DOSAGE: 2 Gm. or 30 grains (N.F.). _Fluidextractum Thujae (Fldext. Thuj.), Fluidextract of Thuja, N.F._--Thuja (100%). Absolute alcohol content about 80 per cent. DOSAGE: 2 Cc. or 30 minims (N.F.). =*Thymol (Thymol), Thymol, U.S.P.=--A phenol. Large, colorless, translucent crystals, having an aromatic thyme-like odor, and a pungent, aromatic taste. Very slightly soluble in water (1:1,010); freely soluble in alcohol (1:1). ACTION AND USES: Antiseptic and anthelmintic. Used chiefly against the hookworm.