This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
I have found alum very useful in infantile diarrhoea when arising from errors in diet, and attended with vomiting, acidity, and green stools: from 1 to 5 gr. may be given with syrup. Diarrhoea dependent upon relaxed conditions of mucous membrane is also cured by alum. Fouquier and others have praised it in enteric fever (Bulletin de Thera-peutique, ix., p. 301), but it is not easily taken, and it is liable to irritate, so that other remedies are usually to be preferred. Alumina, or argilla pura, is placed in the Austrian Pharmacopoeia as an antacid remedy for diarrhoea, especially in children, and is used like bismuth salts. Barthez recommends the single sulphate as preferable.