This section is from the book "Materia Medica Pharmacy, Pharmacology And Therapeutics", by W. Hale White. Also available from Amazon: Materia Medica Pharmacy, Pharmacology And Therapeutics..
They have no action on the unbroken skin, but coagulate the albumin of the discharges from ulcers, sores, etc., and thus form a protecting covering to the parts, and act as efficient astringents. The albumin in the tissues themselves is coagulated also. This coagulated albumin will compress and occlude the vessels, and thus alum is haemostatic. Dried alum absorbs water, and therefore its solid form is mildly caustic. Aluminum acetate (not official) in saturated solution is a very penetrating antiseptic
Alimentary tract. - Alum is an excellent astringent for the mouth, stomach and intestines, and will cause constipation. In large doses it is emetic, acting directly on the stomach, and in larger still, irritant and purgative. Most, if not all, is passed by the faeces; probably, in medicinal doses, it has no more remote effects on the tissues.
Given to animals, in large doses, it produces paresis, loss of sensation, forced movements, drowsiness and death from respiratory paralysis.
Alum is occasionally used as a caustic to destroy weak, exuberant granulations. Kaolin a native aluminum silicate, freed from gritty particles (not official) is a good dusting powder. Fuller's earth of similar chemical composition is used for the same purpose. Kaolin resists most chemical reagents, and therefore it is used as a basis for making pills of such bodies as phosphorus, silver nitrate or potassium permanganate, for with them chemical reaction would occur if an ordinary basis were used. An excellent substitute for poultices is made as follows: Kaolin, 1000 parts, is sifted and sterilized by heat; glycerin, 1000 parts, is added, the heat being continued and mixed by stirring for half an hour. When nearly cool add boric acid, 100 parts, and oil of peppermint, 1; oil of wintergreen, 1; and oil of eucalyptus, 2 parts. Because of its astringency alum has many uses; it may, for example, be applied to weeping ec-zematous surfaces, and as an injection or on moistened lint for vulvitis of children. Solutions of it have been used for leucor-rhcea and gleet. Ten grains ; .60 gm. to the fluid ounce; 30. c.c. of water is a common strength for most purposes. Five grains ; .30 gm. to the fluid ounce; 30. c.c. make a good eye wash or a gargle. Strong solutions, or powdered alum, applied locally, stop bleeding, if it is not severe, such as occurs from piles, leech-bites, slight cuts, the gums and the nose. Aluminum naphtol-sulphonate (alumnol, not official) in 1 to 3 per cent. solutions is an unirritating astringent which, although precipitating albumin, dissolves it when in excess and therefore penetrates below the surface. It is used for the treatment of acute and chronic inflammations of various mucous membranes.
Alimentary canal. - As a mouth wash or gargle 1 - 2 to 100, alum is very valuable in ulcerative stomatitis, in aphthous conditions of the mouth, and in slight pharyngitis or tonsilitis. Alum as a mouth wash attacks the enamel of the teeth. One part of alum with five parts of glycerin, painted on with a camel's hair brush, is excellent for these conditions. If the nose be irrigated with a solution of alum, it may remedy a chronic ozaena. It has been found that other astringents are preferable for bleeding from the stomach and for diarrhoea, but a teaspoonful 4. gm. of alum, dissolved in syrup, and given every quarter of an hour till vomiting is produced, is an excellent emetic for children, and may be used to produce vomiting in laryngitis and bronchitis, as it is non-depressant. Alum whey, obtained from milk curdled by alum, may be given in the diarrhoea of typhoid fever. In lead colic, alum may open the bowels, probably because, being a sulphate, it precipitates any lead salts as insoluble lead sulphates.