Semi-Alternativs, Alkalies. These, before meals, stimulate acid and check alkaline secretions when placed in contact with the mouths of the gland-ducts producing them; when administered after meals, they may be (1) Direct - which lessen the stomach's acidity. (2) Indirect - which have only a remote effect, being oxidized in the blood, and excreted as carbonates in the urine, thereby lessening its acidity: potassium carbonate and bicarbonate, solution of potassium hydroxide, sodium carbonate and bicarbonate, solution of sodium hydroxide, ammonium, lithium, and magnesium carbonates, magnesium oxide, lime water, calcium carbonate, aromatic spirit of ammonia, potassium and sodium acetates, potassium, sodium, and lithium citrates, potassium tartrate and bitartrate, vegetable acids.
Alteratives. These alter or change morbid conditions, by furthering metabolism, and modify nutritive processes: iodine, iodides, arsenic, antimony, mercury, sulphur, sulphides, sulphites, phosphorus, sarsaparilla, guaiacum, mezereum, stillingia, colchicum, xanthoxylum, hydrastis, phytolacca, sassafras, codliver oil. Alteratives also are called Resolvents and Discutients (L. resolvere, to resolve, disperse; dis-cutere, to disperse) from the fact that they promote absorption of inflammatory deposits, either by stimulating the lymphatic glands, or promoting the imbibition of medicinal or nutritive material in the system.
7. Astringents (L. astringere, to draw close, contract). - These contract muscular fibre by direct irritation (local), and condense other tissues by precipitating the albumin and gelatin (remote). 1. Mineral: salts of silver, copper, lead, zinc, bismuth, and aluminum. 2. Vegetable: tannic and gallic acids, nutgall, white oak, geranium, gambir, catechu, kino, krameria, haematoxylon, hamamelis, red rose, uva ursi.