Convallaria,—Lily of the Valley.
Source and Composition. Convallaria Majalis, the "Lily of the Valley," is a well-known perennial of the nat. ord. Liliaceae. It contains two active glucosides, viz.,—Convallamarin, the cardiac-acting principle, soluble in both alcohol and water, and Convallarin, an emeto-cathartic, soluble in alcohol but insoluble in water ; also an acrid Resin, which acts similarly to the latter principle, and probably contains it.
Preparations. Only one is official, viz.:—
- Extractum Convallariae Fluidum, Fluid Extract of Convallaria,—an alcoholic preparation of the whole plant, containing Convallarin. Dose, ♏ij-x.
- *Extractum Convallariae, Extract of Convallaria,—a black solid, freely soluble in water and in alcohol. Dose, gr. ij-x.
- *Infusum Convallariae, Infusion of Convallaria,—probably contains no Convallarin, it being insoluble in water. Dose, ℥ss-ij.
- *Convallamarinum, Convallamarin,—an amorphous, white, bitter powder, soluble in water and in alcohol, but not in ether. Dose, gr. ss-ij.
Physiological Action. Convallaria acts similarly to Squill and Digitalis, being a gastro-intestinal irritant, a cardiac stimulant, and a diuretic. In medicinal doses it slows and strengthens the contractions of the heart, raises arterial tension, slows and deepens the respiration, and increases the urinary discharge. Lethal doses cause irregular cardiac action, with rapid and feeble pulsations; also extreme slowing of the respiration, greatly lowered blood-pressure, and finally arrest of the heart in systole, by direct stimulation of its inhibitory apparatus. Preparations of the root, and alcoholic preparations of the whole plant, are liable to excite emeto-catharsis, which is due to the resin and the Convallarin. The powdered root is sternutatory.
Therapeutics. Long known as an efficient cathartic and diuretic, Convallaria has recently come into prominence as a cardiac tonic, being considered safer than Digitalis, as it has no cumulative action, and does not disturb the stomach or the cerebro-spinal functions, if preparations devoid of Convallarin be used. It has been exceedingly well administered in many forms of heart-disease, particularly in—
- Mitral Stenosis or Insufficiency, characterized by arhythmia, pulmonary congestion, cardiac asthma; also in dropsy due to cardiac disease,—Convallaria has given good satisfaction.
- Aortic Regurgitation,—it relieves many of the most distressing symptoms.
- Valvular Affections of the Heart, generally, when accompanied by dropsy and weak cardiac action,—Convallaria is an efficient remedy.
A Compend of Materia Medica, Therapeutics, and Prescription Writing, 1902, by Sam'l O. L. Potter, M.D., M.R.C.P.L.