Active Ingredients. - The leaves of this tree were ascertained by Procter to yield on distillation both hydrocyanic acid and a light straw-colored volatile oil; the former in quantity sufficient to allow of the product being substituted for cherry-laurel water. Neither of these substances exists in the plant ready formed. They come, as with the cherry-laurel, of the reaction of water with the element amygdaline, during the process of distillation, the changes being induced by another principle also present, the albuminous one called emulsine.

The bark both of the stem and of the roots, especially the latter, also yields hydrocyanic acid. In the fresh state, when alone it should be used (since by keeping its quality deteriorates), it evolves an odor resembling that of peach leaves. The taste is agreeably bitter and aromatic, and resembles that of bitter almonds. An infusion of it, either in cold water or hot, is possessed of all the active properties, but, by boiling, these become in some measure dissipated. There appears also to be some other principle present, of an energetic character, but not yet determined, since an extract of the bark retains its bitterness even when the amygdaline has been wholly withdrawn. Besides the ingredients named, there are resin, starch, tannin, gallic acid, and others.

Physiological Action. - Wild cherry bark is tonic and sedative. The first result, when it is taken in doses not exceeding thirty grains, is quickening of the pulse, which is also rendered fuller and stronger. In certain constitutions, a desire for sleep is induced. To insure the sedative action, it is needful, however, that rather copious use should be made of the medicine.

Taken in large quantities frequently repeated, it impairs the energy of the digestive organs, produces nausea, and has a depressing effect upon the action of the heart and arteries. There are several cases on record in which the frequency of the beats has been reduced from 75 to GO; and in one reported by Stille (he himself being the subject of the experiment) the reduction, effected in a remarkably short time, was from 75 to 50. Both classes of result are attributable of course to the hydrocyanic acid.

The oil is very similar in general properties to the oil of bitter almonds. Two drops administered to a cat caused death in five minutes.

Therapeutic Action. - The value of this medicine has been proved in many ways. It restores tone after the system has been reduced by inflammatory disease, and particularly if the patient suffers from irritation, either general or local. By its use in doses not too large nervous excitability is calmed. In various forms of dyspepsia it is resorted to with advantage, and also in intermittent fevers where the fever lingers on from day to day; here, however, the operation is decidedly not equal to that of cinchona. In America, wild cherry bark has been found efficacious in the hectic fever of scrofula and consumption. It has been extensively employed, and there seems no reason to doubt what is asserted as to its value in this disorder. Good effects are produced also when there is occasion to allay irritable and nervous cough.

In Haemorrhoids wild cherry has been found to be of considerable service, probably from its tonic effect on the intestinal canal.

In the Dyspepsia and Dyspnoea of Cardiac Disease, this remedy has often proved very efficacious. In this country it has been recommended principally by Dr. Clifford Allbutt, who states that many medical men have assured him that, in consequence of his recommendation, they have employed it, and with marked success. But Dr. Allbutt himself remarks that experience has taught him that it is only in comparatively early stages of cardiac disease that Prunus Virginiana acts with decided effect. In the later and more confirmed conditions of this complaint it may be usefully replaced by the subcutaneous injection of morphia.

Preparations And Dose. - Extractum Pruni Virginianae Fluidum, 3 ss. - j. (2.- 4.); Syrup. Pruni Virg. 3 ij. - iv (10. - 20.); Infus. Pruni Virgin. 3 j. - ij. (30. - 60.).