446. Apocynum.—Apocynum, N.F. Canadian Hemp.
The dried rhizome of Apocy'num canna'binum Linné without the presence of more than 5 per cent, of stems and foreign matter.
BOTANICAL CHARACTERISTICS.—Stems much branched, 2 to 3 feet high. Leaves from oval to oblong or lanceolate, short petiolate or sessile. Inflorescence cymose; corolla greenish-white, with nearly erect lobes, the tube not longer than the calyx tube.
HABITAT.—United States.
DESCRIPTION OF DRUG.—A long, cylindrical root, somewhat contorted, about 8 mm. (1/3 in.) thick, with a rather thick light brown bark, longitudinally wrinkled and transversely fissured, and a yellowish, porous wood divided by fine medullary rays into very narrow wood-wedges; fracture short. The thick inner cortical layer has numerous lactiferous vessels scattered through it, which in the fresh state secrete a milky Juice which hardens into a caoutchouc-like substance, Odor slight, or none; taste bitter, nauseous.
Apocynum androsaemifolium Linné, dogbane, resembles the above, but has a relatively thicker bark inclosing a white, porous wood, and contains, in the outer portion, stone-cell groups. By applying the phloroglucin test to a section, the groups of stone-cells are revealed, stained red. Two species sold indiscriminately.
CONSTITUENTS.—Apocynein, a yellowish glucoside (acting like digitalin); apocynin, a bitter, resin-like extractive; tannin, resin, starch, etc.
ACTION AND USES.—A valuable diuretic in moderate doses, in large doses emetic and cathartic, producing considerable diaphoresis and expectoration; most used and most beneficial in dropsy. Recently the drug has attracted some attention as a most valuable deobstruent in relieving renal congestion in the second stage of tubular nephritis, It is also a decided heart tonic. Dose as a diuretic, 4 to 5 gr. (0.3 to 0.324 Gm.); as an emetic and cathartic, is to 30 gr. (1 to 2 Gm.).
- OFFICIAL PREPARATION.
- Fluidextractum Apocyni. Dose: 15 drops (1 mil).