Page 226 - My FlipBook

224 DENTAL MEDICINE.
acid and astringent taste. Gallic acid is slightly soluble in cold
water, and freely soluble in hot water, glycerine or alcohol.
Galls, from which gallic acid is prepared, are the excrescences
caused by the punctures and deposited ova of a hymenopterous
insect on the twigs of the gall oak (^ercus Infectorid).
Source.— Galls are obtained from Asia Minor and Persia.
Medical Properties and Action of Galls.—Powerfully astringent,
this property depending upon the presence of tannic and gallic
acids, as they contain 35 per cent, of tannic and 5 per cent, of
gallic acids. The powder, which is obtained from the small,
round, dark-blue or lead-colored excrescences, is of a light yel-
lowish-gray color, inodorous and of a bitter taste.
Galls are used in various forms, such as powder, tincture, in-
fusion, ointment, etc.
Therapeutic Uses.—Galls are employed in the treatment of
chronic diarrhcea, dysentery, leuchorrhoea, chronic gonorrhoea and
gleet, diseases of the uterus and intermittent fevers, and externally
in hemmorrhagic disorders, hemorrhoids, relaxation of uvula, hy-
pertrophy of the tonsils, etc.
Gallic acid is given directly for internal hemorrhage.
Dose.—Of powdered galls, gr. x to gr. xx. The ointment is
composed of: powdered galls, gr. Ixxx ; benzoated lard, .^j. It
is combined with opium in the proportion of ointment of galls,
5j ; powdered opium, gr. xxxij.
Medical Properties and Action.—Gallic acid is a powerful as-
tringent for arresting hemorrhage in which the bleeding vessels
must be reached through the circulation. It is also a valuable
styptic in cases of hemorrhage depending on a hemorrhagic dia-
thesis, and in the form of a gargle it is very serviceable in acute
inflammations of mucous membranes. It is also a strongly de-
odorizing agent ; and, like tannic acid, it is capable of taking
oxygen from the blood globules. Internally employed it produces
constipation, which may be prevented by an occasional aperient.
Although it is weaker than tannic acid, yet its properties are very
similar. It is supposed to be converted into tannic acid in the
blood.
Therapeutic Uses.— Gallic acid is employed in the treatment