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..
The therapeutical applications of tannic acid are very numerous. It is used as an astringent for ulcers, sores, various moist eruptions, tonsillitis, pharyngitis, nasal catarrh, otorrhoea, gastric catarrh, diarrhoea (large doses of 30 gr.; 2 gm. may be given, and catechu and logwood are favorite remedies), leucorrhoea, gonorrhoea, rectal ulcers, fissures, and prolapse. It is employed as a haemostatic in bleeding from small wounds, ulcers, the gums, the pharynx, the nose, the stomach, the intestine, haemorrhoids, and the bladder. Whenever practicable a good method of application is to dust it on the part, especially for a haemorrhage; if this is gastric or intestinal, 30 gr.; 2. gm. or more should be frequently given by the mouth. For external use or application to the throat the glycerite is useful. A gargle of the gly-cerite in water, 1 to 8 may be made. The troches are convenient for pharyngitis. A spray (1 to 2 in 96 of water) or an insufflation of tannic acid and starch may be used for the mouth and larynx. The ointment of nutgall and opium, 1 to 14 of ointment of nutgall, is a favorite application for piles. The suppositories 3 gr.; . 20 gm. each are useful for rectal discharges. Solutions 1 to 48 in water may be injected into the urethra for urethritis and gonorrhoea, and into the bladder for cystitis. It should never be used hypodermatically. The decoction of oak bark, employed as a high rectal injection, destroys the threadworm. A preparation of nutgall dissolved in glycerin was formerly used as an injection into hernial sacs (Heaton's method). The temporary results were excellent, but sooner or later failures occurred in a very large percentage of cases.
It is a tasteless, odorless powder, insoluble in water, and is believed to pass -unchanged through the stomach and to be slowly decomposed in the intestines, thus exerting an astringent effect in them. The dose is 5 to 30 gr., .30 to 2.00 gm. in wafers.
Tannalbin (not official) is a tannin albuminate which has been subjected to a dry heat of 2300 - 2480 F. (110°-120° C.) for several hours. It is a faintly yellow, tasteless powder containing about 50 per cent. of tannic acid. Laboratory experiments have shown that it is not easily decomposed by an artificial gastric juice, but it is rapidly separated into its constituents in an alkaline medium or by an artificial solution of the pancreatic ferments. This preparation then passes through the stomach unchanged, and may not be broken up until it has passed well down into the intestine. The dose is 5 gr., .30 gm., given in wafers at frequent intervals.