A balsam obtained from Myroxylon Pereirae. It exudes from the trunk of the tree after the bark has been beaten and scorched and removed. Salvador in Central America.

Characters. - A treacle-like liquid, nearly black in bulk, reddish-brown and translucent in thin films; of syrupy consistence, balsamic odour, and an acrid, slightly bitter taste.

Composition. - Contains resin, volatile oil, and both benzoic and cinnamic acids.

Dose. - 10 min. to 1/2 fl. dr., and upwards, made into an emulsion with mucilage or yolk of egg.

Action and Uses. - It is employed locally as a parasiticide in scabies and in cases of skin-diseases depending on vegetable fungi. It destroys both the itch-acarus and its eggs. It is much more agreeable than sulphur ointment. Before applying it, it is advantageous to take a warm bath, and wash the affected parts thoroughly with soft soap, and then to rub it well in all over the body, especially into the armpits, between the fingers, and on the inside of the thighs. The treatment should be repeated every two or three days, during which time the same linen should be worn; this when cast off should be well disinfected, or the disease may return. It may be used either alone or in combination with petroleum to destroy pediculi; a useful formula is - balsam of Peru, 20 parts; olive oil, 50; petroleum, 100 parts. It is also useful in prurigo, in pruritus, and in the later stages of an acute eczema. It is a useful stimulant to bed-sores and ulcers. It is given internally to lessen discharge from mucous membranes, as in bronchorrhoea, gleet, and leucorrhoea; also as a stimulating expectorant in chronic bronchitis.