Eucalyptus or red gum is in exudation from the bark of Eucalyptus rostrata, Schlecht (N.O. Myrtaceae), and other species of Eucalyptus. It is a variety of Botany Bay kino (see Kino Eucalypti). The trees are natives of Australia, whence the gum is exported. It is obtained by incising the tree, and inserting a trough-shaped piece of tin, by means of which the treacly liquid flows into buckets or tins, when it becomes dry within a few days. It is also found in the dry state in cavities in the trunks of the trees. The gum should be in small, dark reddish-brown, opaque, and more or less dusty pieces, which yield a pale red powder. When chewed it is tough, has an astringent taste, and adheres to the teeth, colouring the saliva red. Cold water should dissolve from 80 to 90 per cent. Bright ruby-coloured gum is less soluble, and not so suitable for medicinal use.
Constituents.—The chief constituent of eucalyptus gum is tannin (kinotannic acid), of which it contains about 47 per cent. Other constituents which may be present are a phlobaphene (kino red), a gelatinisable tannin-glucoside, catechin, and pyrocatechin (catechol).
Action and Uses.—Eucalyptus gum is a valuable astringent to the throat, and is administered in the form of lozenges land pastilles. Its action is similar to that of kino, but weaker and more prolonged. Trochiscus Eucalypti Gummi is the official lozenge; other combinations are with potassium chlorate and cubebs, or with cocaine and menthol. Extractum Eucalypti Gummi Liquidum is an astringent and styptic solution; injected into the nose or applied to wounds on lint, it stops haemorrhage. Diluted with 16 parts of water it is used as an astringent gargle, or with 40 parts of water as an astringent injection. The tincture is used similarly. The powdered gum, the tincture, and the liquid extract are used Internally as astringents in diarrhoea and dysentery. An astringent syrup prepared from the gum is added to gargles, or given internally.
Dose.—1 to 3 decigrams (2 to 5 grains).
- Extractum Eucalypti Gummi Liquidum, B.P.C.—LIQUID EXTRACT OF EUCALYPTUS GUM. Syn.—Extractum Gummi Rubri Liquidum; Liquid Extract of Red Gum. 1 in 4.
- Used as a styptic, applied to wounds on lint, or injected into the nose for epistaxis. Dose.—2 to 4 mils (30 to 60 minims).
- Gargarisma Eucalypti Gummi, B.P.C.—EUCALYPTUS GUM GARGLE. 1 (liquid extract) in 16.
- Used as an astringent gargle.
- Injectio Eucalypti Gummi, B.P.C.—INJECTION OF EUCALYPTUS GUM. 1 (liquid extract) in 40.
- Used as an astringent injection.
- Pessus Eucalypti Gummi, B.P.C.—EUCALYPTUS GUM PESSARY. 10 grains.
- Suppositoria Eucalypti Gummi, B.P.C.—EUCALYPTUS GUM SUPPOSITORIES. 5 grains.
- Syrupus Eucalypti Compositus, B.P.C.—COMPOUND SYRUP OF EUCALYPTUS. Syn.—Syrupus Eucalypti Rostratae.
- Eucalyptus gum, from Eucalyptus rostrata, 7.5; oil of eucalyptus, 0.26; with refined sugar, mucilage of gum acacia, and distilled water, to 100. Used for its astringency, being given internally in diarrhoea and dysentery, and diluted with seven times its volume of water for application as a gargle. Dose.—2 to 4 mils (1/2 to 1 fluid drachm).
- Syrupus Eucalypti Gummi, B.P.C.—SYRUP OF EUCALYPTUS GUM. Syn.—Syrupus Gummi Rubri; Syrup of Red Gum.
- Liquid extract of eucalyptus gum, 62.5; refined sugar, 37.5. This preparation resembles Syrupus Eucalypti Compositus in its properties. It is given internally as an astringent, and is used diluted with 7 parts of water as a gargle for inflamed throats. Dose.—2 to 4 mils (1/2 to 1 fluid drachm).
- Tinctura Eucalypti Gummi, B.P.C.—TINCTURE OF EUCALYPTUS GUM. Syn.—Tinctura Gummi Rubri; Tincture of Red Gum. 1 in 4.
- Given as an astringent in diarrhoea, and added to gargles for inflamed throats. Dose.—1 to 2 1/2 mils (15 to 40 minims).
- Trochiscus Eucalypti Gummi, B.P.—EUCALYPTUS GUM LOZENGE.
- Each lozenge contains eucalyptus gum, 65 milligrams (1 grain); with fruit basis. Eucalyptus gum lozenges are used as an astringent for sore mouth and throat. Dose.—1 to 6 lozenges.
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.