This section is from the book "Botanic Drugs Their Materia Medica, Pharmacology and Therapeutics", by Thomas S. Blair. Also available from Amazon: Botanic Drugs, Their Materia Medica, Pharmacology and Therapeutics.
Acacia, Gum Arabic, Acacia Senegal and A. Varek (Ninth Rev.). A gummy exudation, of demulcent properties, and used as a suspending agent. The U. S. P. mucilage of acacia is commonly used, but it is precipitated by alcohol, and the lime water in it precipitates alkaloids. Alkaloids would better be added to the syrup of acacia. Mucilage of tragacanth is not precipitated by alcohol. Extract of malt is displacing these gums to carry acid and bitter drugs.
Acacia Cortex, the bark of A. Arabica, is official in England. Its decoction is used in doses of one-half to two fluid ounces as an astringent.
Acacia Catechu, formerly official, was known as catechu. Its preparations were not stable, and Gambir, Ourouparia gambir, took its place.