Botanical name: 

The wood of Picrasma excelsa (Swartz), Planchon (Nat. Ord. Simarubaceae). A tall tree of Jamaica and neighboring islands. Dose, 10 to 30 grains.
Common Names: Quassia, Quassia Wood, Bitter Wood.

Principal Constituent.—The bitter substance quassiin (quassin).
Preparations.—1. Infusum Quassiae, Infusion of Quassia (1 drachm to 7 ounces of cold water). Dose, ½ to 2 fluidounces.
2. Specific Medicine Quassia. Dose, 1 to 30 drops.

Action and Therapy.—Quassia is a bitter stomachic and tonic. A cold infusion (1 to 100 of cold water) used as an injection is one of the most useful agents to remove ascarides. An acidulated infusion may be employed to lessen the craving for alcoholics. For this purpose the wood may be extracted with vinegar and administered in drachm doses in a glass of water. Specific medicine quassia may be given in doses of one to thirty drops, in water, for impairment of the appetite in feeble and emaciated persons. Cold infusions of the chips are to be preferred to hot, as less extractive matter is drawn out.

Quassia is not without danger, and established doses must not be exceeded. Even rectal injections of it have caused collapse in a child. Having no tannin, quassia may be given with iron, if desired.

The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.