Balsamum Peruvianum, B.P. Balsam of Peru.
Balsam of Peru is an oleoresinous liquid obtained from the trunk of Myroxylon Pereira, Klotsch. (N.O. Leguminosae), a tree growing in the forests of San Salvador in Central America. It is also official in the U.S.P. The formation of the balsam, which is not a normal secretion of the tree, is induced by gently beating the bark, and subsequently scorching it. As the balsam exudes it is soaked up by rags, with which the wounded places are covered; these are pressed, and the crude balsam so obtained purified by boiling with water. The drug is exported chiefly from Acajutla and Belize to New York and Hamburg. Balsam of Peru occurs as a dark brown, viscid, but not glutinous, liquid, which is transparent and of a reddish-brown colour in thin layers. It has an agreeable aromatic odour and a bitter, acrid taste with persistent after-taste. The specific gravity of genuine balsam of good quality varies from 1.140 to 1.153 (U.S.P., 1.140 to 1.150 at 25°). The commoner adulterants, such as alcohol, kerosene, fixed oil, turpentine, copaiba, etc., lower the specific gravity perceptibly. Genuine balsam of Peru may be distinguished from factitious or so-called synthetical balsam by the following test:—Shake 2 grammes of the balsam with 10 mils of petroleum spirit, evaporate the spirituous solution in a clean porcelain dish, dry on a water-bath, cool, and mix with 2.5 decimils (0.25 milliliters) of nitric acid (specific gravity, 1.38). Genuine balsam will give a golden-yellow colour.
Soluble in absolute alcohol (1 in 1), chloroform, or glacial acetic acid, but only partially soluble in ether. Water shaken with the balsam removes only traces of cinnamic acid.
Constituents.—Balsam of Peru consists chiefly of from 56 to 66 per cent. of a colourless, aromatic oily liquid (cinnamein) and about 28 per cent. of a dark resin. The liquid portion is a mixture of benzyl benzoate and benzyl cinnamate in varying proportions, the former usually preponderating; the resin consists of a resin alcohol (peru-resinotannol), combined with cinnamic and a little benzoic acid. The drug contains, in addition, an alcohol (peruviol) which possesses a sweet odour and taste, together with traces of vanillin and free cinnamic acid.
Action and Uses.—Balsam of Peru is used internally as an antiseptic and expectorant., applied externally it acts as an antiseptic and parasiticide, especially in scabies. It was at one time much used in phthisis, on the supposition that it induced cicatrization of the tuberculous nodules, but it has no such effect. Its action resembles that of benzoic acid. For internal administration it may be prepared either in a mixture or in pills. An emulsion is made with the aid of half its weight of powdered gum acacia in the same manner as with a fixed oil, or the emulsion may be made with yolk of egg. When required in pills it may be combined with a little calcined magnesia or slaked lime, and allowed to stand for two or three hours before rolling the mass; or, if the quantity of the drug is small, it may be mixed with powdered liquorice root and a little treacle. For external use it is employed as an ointment. It is, however, sometimes applied in skin diseases, especially in scabies, in the pure state, or mixed with an equal quantity of castor oil. For suppositories the basis should be oil of theobroma, with sufficient white wax to counteract the softening effect of the balsam.
Dose.—3 to 10 decimils (0.3 to 1.0 milliliters) (5 to 15 minims).
- Collodium Peruvianum, B.P.C.—BALSAM OF PERU COLLODION. 1 in 10.
- Unguentum Peruvianum, B.P.C.—BALSAM OF PERU OINTMENT. 1 in 8.
- Applied as a parasiticide for scabies and pediculi, and in some skin diseases.