2715. Astringents are medicines given for the purpose of diminishing excessive discharges, and to act indirectly as tonics. This class includes catechu, kino, oak bark, logwood, rose-leaves, chalk, and white vitriol.

Catechu

2716. Catechu is a most valuable astringent.

It is used externally, when powdered, to promote the contraction of flabby ulcers. As a local astringent it is useful in relaxed uvula, a small piece be ing dissolved in the mouth; small, spotty ulcerations of the mouth and throat, and bleeding gams, and for these two affections it is used in the form of infusion to wash the parts.

It is given internally in diarrhoea, dysentery, and hasmorrhage from the bowels.

Dose, of the infusion, from one to three ounces; of the tincture, from one to four drachms; of the powder, from ten to thirty grains.

Caution. - It must not be given with soda or any alkali; nor metallic salts, albumen, or gelatine, as its property is destroyed by this combination.

Kino

2717. Kino is a powerful astringent. It is used externally to ulcere, to give tone to them when flabby and discharging foul and thin matter.

It is used externally in the same diseases as catechu.

Dose, of the powder, from ten to thirty grains; of the tincture, from one to two drachms; of the compound, powder, from ten to twenty grains; of the infusion, from a half to one and a half ounce.

Caution. - (See Catechu.)

Oak Bark

2718. Oak Bark is an astringent and tonic.

It is used externally, in the form of decoction, to restrain bleeding from lacerated surfaces.

As a local astringent it is used in the form of a decoction as a gargle in sore throat and relaxed uvula.

It is used internally in the same diseases as catechu, and when combined with aromatics and bitters, in intermittent fevers.

Dose, of the powder, from fifteen to thirty grains; of the decoction, from two to eight drachms.

Logwood

2719. Logwood is not a very satisfactory astringent.

It is used internally in diarrhoea, the last stage of dysentery, and a lax stato of the intestines,

Dose, of the extract, from ten to one drachm: of the decocticn, from one to three ounces, three or four times a-day

Rose Leaves

2720. Rose leaves are astringent and tonic.

They are used internally in spitting of blood, haemorrhage from the stomach, intestines, etc, as a gargle for sore throat, and for the night sweats of consumption.

The infusion is frequently used as a tonic with diluted sulphuric acid (oil of vitriol), after low fevers.

Dose of infusion, from two to four ounces.

Chalk

2721. Chalk, when prepared by washing, becomes an astringent as well as antacid.

It is used internally in diarrhoea, in the form of mixture, and externally as an application to burms, scalds, and excoriations.

Dose of the mixture from one to two ounces.

White Vitriol

2722. White vitriol, or sulphate of zinc, is an astringent, tonic, and emetic-It is used externally as a collyrium for ophthalmia (See "Domestic Pharmacopoeia, 906), and as a detergent for scrofulous ulcers, in the proportion of three grains of the salt to one ounce of water.

It is used internally in indigestion, and many other diseases; but it should, not be given unless ordered by a medical man, as it is a poison.