Origin. - The concrete, saccharine exudation of Fraxinus Ornus L., a slender tree indigenous on the northern shore of the Mediterranean from Asia Minor west to Spain.

Description and Properties. - Flattish, somewhat three edged pieces, about 8 inches (20 Cm.) long and 2 inches (5 Cm.) broad (usually smaller), friable, externally yellowish-white, internally white, porous, and crystalline; or fragments of different sizes, brownish-white, and somewhat glutinous on the surface, internally white and crystalline; odor honey-like; taste sweet, slightly bitter, and faintly acrid. Manna contains a resin, the purgative principle, besides mannite, fraxin, and sugar.

Dose. - 1/2-1 ounce (16.0-32.0 Gm.) [1/2 ounce (16 Gm.), U. S. P.], dissolved in hot water.

Official Preparation

Infusum Sennae Compositum - Infusi Sennae Compositi - Compound Infusion of Senna. - See Senna.

Physiological Action and Therapeutics. - Manna is a laxative, cholagogue, and nutrient. Its mild laxative action renders the drug peculiarly efficient in constipated conditions of pregnant women, and children and persons suffering from piles or irritation of the genito-urinary tract.

The drug is slow in its action, tending to confine the bowels after the primary laxative effect.