Guaiaci Lignum - Guaiacum: Wood. - The wood of Guaiacum officinale. Imported from St. Domingo and Jamaica, and reduced by the turning lathe to the form of a coarse powder or small chips.

Guaiaci Lignum is an ingredient of Decoctum Sarsae Com-positum. (See Sarsa Radix, page 354.)

Guaiaci Resina - Guaiacum Resin. - The resin of Guaiacum officinale. Obtained from the stem by natural exudation, by incisions, or by heat.

Characters. - In large masses of a brownish or greenish-brown colour; fractured surface resinous, translucent at the edges; with pleasant aromatic odour and burning taste. Insoluble in water; soluble in alcohol, ether, chloroform, and alkaline fluids. A solution in rectified spirit strikes a clear blue colour when applied to the inner surface of a paring of raw potato.

Substances resembling Guaiacum Resin: Myrrh, Scammony, Benzoin, Aloes, Resin, which have no green tinge.

Composition. - The chief constituent of guaiacum wood is the officinal resin, with a crystalline bitter colouring matter, gum, etc. The resin is itself composed of three resins, guaia-conic acid, C19H10O5, 70 per cent.; guaiac acid, C6H8O3, re-sembling benzoic acid; and guaiaretic acid, C20H16O4, 10 per cent, with an indifferent resin.

Incompatibles. - Mineral acids, spirit of nitrous ether. Dose. - 10 to 30 gr.

Preparations.

1. Mistura Guaiaci

Mistura Guaiaci. Guaiacum Resin, 2; Sugar, 2; Gum Acacia, 1; Cinnamon water, 80. Dose, 1/2 to 2 fl.oz.

2. Tinctura Guaiaci Ammoniata, - 1 in 5 of Aromatic Spirit of Ammonia. Dose, 1/2 to 1 fl.dr., with 1 drachm of mucilage or yolk of egg.

3. Pilula Hydrargyri Subchloridi Composita

Pilula Hydrargyri Subchloridi Composita. 1 in 2 1/2. (See Hydrargyrum, page 86.)

Action And Uses. 1. Immediate Local Action And Uses

Internally, guaiacum is a local stimulant, producing salivation, an acrid hot sensation in the throat, warmth in the epigastrium, increase of the movements and secretions of the stomach and bowels, and reflex stimulation of the heart. In large quantity it is a gastro-intestinal irritant, causing powerful vomiting and purging, and the attendant disturbances of the system generally.

Guaiacam powder frequently relieves sore throat, if given in 30-grain doses, to be placed on the tongue, and slowly swallowed every six hours. The tincture or non-officinal lozenge is less successful. Plummer's pill doubtless owes part of its mildly purgative effect to the guaiac resin it contains.

2. Action On The Blood, Specific And Remote Local Action And Uses

The further action of guaiacum physiologically is still obscure. Besides its stimulant effect on the circulation already mentioned, it appears to increase the secretions of the skin and kidney, and probably stimulates the liver and metabolism generally. In the form of the ammoniated tincture it is used in chronic gout and rheumatism, certainly with much success in some cases. As a constituent of Decoctum Sarsae Com-positum, not alone, it is given as an alterative in syphilis.