By DR. E. R. SQUIBB.
Rhamnus Purshiana is a sub-variety of the Buckthorn family of small trees and shrubs, which grow in most of the temperate climates. This sub-variety grows abundantly in California and Oregon, and the bark under the name of Chittem bark or cascara sagrada has been long known and used as a purgative, and the name cascara sagrada has more recently been usefully contracted to cascara. Some years ago it was taken up and pushed as a novelty, and by vigorous advertising, as a panacea for numerous ills, it has come into very common use, in the form of several pharmaceutical preparations.
There seems to be no doubt but that the bark of the branches, and a welt-made fluid extract, and extract of this bark, are all effective simple aperients, not very disagreeable in taste or effect, easy of management, and not very liable to lose their effects by continuous use. And a prominent advantage in their use is that the dose may be adjusted in each individual case to any degree of activity or mildness without leaving a persistent reaction.
These peculiar characteristics have long been known as belonging peculiarly to the bark of Rhamnus Frangula, and the use of this both in Europe and this country long antedated the use of cascara sagrada. And this longer and better known variety of the Buckthorn family was admitted to the present revision of the pharmacopoeia, because it was supposed to be the better medicinal agent of the two. Its supposed advantages over cascara are that while having all the advantages of cascara, it is milder, more pleasant and more manageable in effect and more agreeable in. taste, and less liable to disturb stomachs and intestines which are sensitive or irritable. When properly used both are simple, mild, agreeable aperients, but the buckthorn the more simple and agreeable of the two, and required in somewhat larger quantities to give the same effect. Hence one or the other is superfluous in the materia medica, and it becomes important to know which should have the preference.
In order to assist in determining which is the better, large quantities of the two barks were carefully selected of uniform good quality, and from these exactly parallel extracts and fluid extracts were made, and have been placed in the hands of many close and careful observers, who are as little prejudiced as may be by the florid advertising, which one of the agents has received. By the parallel observations of many, made independently, it is hoped to obtain useful, if not conclusive, testimony.
Both barks are very plentiful and very cheap, and good qualities are easily obtainable of either at a cost of not more than eight or nine cents per pound by the bale. The buckthorn is much more uniform in quality than the cascara, and the inferior qualities of this, which are offered at five to seven cents per pound, are better than the inferior qualities of cascara at similar prices. Both come long distances, and the freight on the buckthorn from Germany is less than upon cascara from California, and how it is possible to pay freights and two or three profits on them and sell them at such prices, is not easy to comprehend. The very different and inferior bark of the trunks and larger branches are rarely or never seen in buckthorn. But the markets are full of such bark from the cascara, and it is difficult to get even a few bales of the smaller quill bark which should alone be used. Both barks are said to improve very much in their medicinal qualities by age, and if so, it is reasonable to suppose that the preparations made from them also improve by age, but probably not so much as the barks do. Neither bark should be used until it is over a year old in the dry state, and this condition is more easily secured in the case of buckthorn than cascara.
The menstruum used for exhausting these barks by repercolation is important, and that which the writer has for many years used with buckthorn has been very successful. And there is hardly an instance known wherein the process of repercolation is more important or more successful. In another part of this pamphlet an example is given in detail of the management of buckthorn, and cascara was and is treated in exactly the same way with corresponding results, as far as the process is concerned.
This process gives preparations easily miscible with water, wine or syrup, and therefore easily taken and easily appropriated by the stomach and first passages.—Ephemeris, Oct. 1887, page 984.
In the same number of Ephemeris, page 1045, Dr. Squibb has an elaborate article of Fluid Extract of Rhamnus Frangula. The menstruum is a mixture of 25 per cent. alcohol, 5 per cent. glycerin, and 70 per cent. water. The bark in No. 20 powder is moistened with 75 per cent. of its weight of this menstruum; after maceration for twenty-four hours the bark is brought back to about its original condition of moisture and has swelled to the maximum. It is then sifted and packed firmly and allowed to percolate at the rate of about 60 drops per minute, when the quantity of the dry bark is about two pounds, or a kilogram. The preparation is finished by repercolation, no heat being employed.