Related entry: Agaric acid
White or larch agaric is the dried fungus, Polyporus officinalis, Fries (N.O. Hymenomycetes), which grows upon Larix sibirica, Led., and L. europaea, DC. (N.O. Coniferae), and other species of larch. It is collected chiefly in the larch forests near Archangel, then dried and exported to Hamburg. It occurs in light, somewhat spongy, resinous pieces of irregular shape, greyish to brown externally, yellowish-white internally, about 20 centimetres in height and 15 centimetres in thickness. It has a faint odour, and a sweetish taste, which is afterwards acrid and bitter. The pieces are very friable, but not easily powdered.
Constituents.—The drug contains agaric acid (agaricin), agaricol, a phytosterol, ricinoleic acid, cetyl alcohol, and several resinous principles.
Action and Uses.—White agaric is an irritant, and may cause nausea, vomiting, and purging. It is used in the preparation of Tinctura Antiperiodica.
Dose.—2 to 20 decigrams (3 to 30 grains).