Rheum Palmatum. Rhubarb.

Description: Natural Order, Polygonaceae. In the same Family with smart weed and yellow dock. A plant with perennial roots, and annual herbaceous stems; native to Tibet and Chinese Tartary, but now much cultivated through all Asia and in Turkey. One species, sported into several varieties, is extensively cultivated in Europe and America under the common names of pie-plant and garden rhubarb. Genus RHEUM: Corolla wanting; calyx petaloid, six-parted, withering. Stamens nine, inserted into the base of the calyx; styles three, reflected; stigmas peltate, entire. R. PALMATUM: Leaves large, roundish-cordate, half palmate; lobes pinnatifid, acuminate; dull green, uneven and much wrinkled above, minutely downy beneath; petioles pale green, marked with short purple lines, round, obscurely channeled above. There are several other species of Asiatic rhubarb, which furnish a medicinal root; of which the UNDULATUM has oval and wavy leaves that are quite downy beneath, and blood-red and downy petioles; and the COMPACTUM has thick, heart-shaped, smooth, and almost shining leaves, and green petioles which are slightly compressed at the sides. The undulatum was long considered the best, but that distinction is now accorded to the palmatum; though it is probable that there are but few differences between the three.

The root of this article is gathered in the latter part of summer, from plants which are six years old. It varies in diameter from an inch and a half to three inches at the collum, gradually tapering, somewhat porous, covered with a thin dirty-brown cortex, yellow or brownish-yellow within, and of a peculiarly agreeable and rather spicy aroma. After being dug and washed, the cortex is peeled or scraped off, a hole bored through the center and the roots strung on threads, and then dried in the sun. Two leading qualities come to market, as follows:

Russian or Turkey Rhubarb. This has been furnished through the medium of a treaty between the Russian and Chinese governments, by which the former received in barter all the rhubarb grown in Buchara and Tartarian China, accepted only such as passed satisfactorily under the inspection of a Medical Commission from Russia, and burnt all inferior samples. It came to market either by way of St. Petersburg or Constantinople, and its superior excellence was uniformly insured by the rigidity of inspection. It is in somewhat roundish pieces, three to four inches long, flattened irregularly from having the cortex sliced off, yellow mixed with reddish- white externally, yellow marbled with grayish and reddish wavy lines internally, light, of a rather bitter and but faintly astringent taste, somewhat gritty under the teeth, and of a strong aroma. It is imported in square chests covered with a hempen cloth and then a hide; and the pieces are usually covered with a fine yellow dust. This is by far the choicest article, and yields a light yellow powder.

East Indian or Chinese Rhubarb. This is exported from Canton, Shanghai, and other parts of Eastern China. It is usually in somewhat top-shaped pieces, smooth and round from having the cortex scraped off rather than peeled, more dense than the Russian, dull yellow or yellowish- brown without, the veins of a dull reddish-brown; the aroma much fainter, and the taste less bitter but more astringent, than the Russian. Some pieces are worm-eaten, and these are of inferior quality. An angular-looking quality is imported from Singapore, which in the rough resembles the Russian; but may be distinguished by its duller color and less marked aroma. The great cost of the Russian variety, brings the Indian rhubarb into most general use; and the difference in medical power is too limited to justify the purchase of the former in lieu of a good quality of the latter. Yet the poor qualities of India rhubarb are of little worth; and its powder is so almost universally adulterated with an inferior English article, as well as being made from rejected roots, as seldom to represent more than half the strength of a good article. At present, the powder of rhubarb is extensively adulterated with flour and colored with turmeric.

RHEUM RHAPONTICUM is the species now so much cultivated in the gardens of Europe and America for its very large and acidulous petioles, which are used in early spring for family pies. By cultivation, several varieties have been produced; of which the principal are known among gardeners as Linnaeus, Victoria, and Calhoun. Its root is gathered from the fourth to the sixth year. It has a muddy yellowish-red epidermis, beneath which the root has a pinkish-yellow hue, and internally has parallel pinkish veins. The density is less than that of the Asiatic species, and the center of the root is sometimes soft and even spongy. The odor of this species is faint, and not so agreeable as that of the foreign roots; the taste is bitterish astringent, mucilaginous, and not gritty nor always pleasant.

Rhubarb contains a yellow coloring matter, volatile oil, tannic and gallic acids, and peculiar aromatic and bitter principles. Water acts on it rather freely; diluted alcohol much more effectually; and solutions of potassa, soda, and ammonia act on it thoroughly, changing the liquid to a deep red or brownish red by the solvency of the alkaline agents upon a yellow granular principle of an acid character, called crysophonic or rheic acid, or rhein. The red veins contain the tannic acid, whence the redden-hued roots are most astringent. Crystals of oxalate of lime, quite insoluble in water, also exist in the root; and the presence of starch is shown in all species, and especially in the rhaponticum, by iodine.

Properties and Uses: Turkey (Russian) rhubarb is the officinal standard, but the cheaper Indian root has almost superseded it. The two are nearly the same in general action; but the Turkey is pleasanter, a little less astringent, and of greater relative strength. The English and American, as above mentioned, are less agreeable to the taste, somewhat more astringent, and distinctly mucilaginous; yet their general impression upon the system is nearly identical with the foreign species, though about twice the quantity is required. I have used this for several years, and am well pleased with it; and think that, by due care in its cultivation, and the selection of a proper variety, the profession would find a suitably efficient quality of rhubarb at their own doors.

Rhubarb root has the peculiar character of combining in itself relaxant, stimulant, and astringent powers–the first two enabling it to prove mildly tonic, and the last diminishing mucous discharges and leaving behind a full astringent impression. Its action is mild, its taste not unpleasant but rather agreeable to the stomach, and its impression on the alvine mucous membranes peculiarly soothing. The saliva is soon colored yellow by it; the faeces also become yellow in from ten to twenty hours, or when the rhubarb has fairly passed through the bowels; and it may even color the urine and the perspiration–both which secretions may leave a yellow stain upon the linen. In doses of from four to eight grains three times a day, it soothes irritability of the stomach and promotes digestion; and often proves peculiarly serviceable in those forms of indigestion which are accompanied by acidity, laxity of the gastric structures, morning looseness of the bowels, and sallow countenance. A portion of its good effects are due to its mild stimulation of the gall-ducts, leading to the ejection of bile. Doses of from twenty to forty grains prove gently laxative, increasing peristaltic motion, procuring the dislodgment of scybala or other offensive materials, and not causing exhaustion at any time. In sensitive persons, or when the alvine canal is sensitive, large doses occasionally cause griping; and in febrile conditions they not unfrequently accelerate the pulse. The alvine discharges it procures are never watery, but rather consolidated; and its action is peculiarly beneficial in diarrhea and dysentery by first procuring the dislodgment of crude materials, and afterwards gradually diminishing the fluidity of the discharges. The principal use now made of it, is for this class of cases, and for all other cases where the bowels are prone to looseness; the better method usually being to give two medium laxative doses (of about twenty grains each) at intervals of three hours, so as to procure the evacuation of alvine accumulations, and, when the stools become yellowish, showing that the rhubarb has passed through the bowels, to continue doses of from three to five grains at intervals of three or four hours for the astringent- tonic effect. If the alvine crudities have been removed previously, the cathartic doses are not to be given. The tendency of this agent to leave astringency, rarely produces constipation; yet is sufficient to make it unadvisable to use it as a common physic, though it is well adapted to children of a scrofulous habit with tumid abdomens. It is in similar cases that its tonic action is of most service; for it seems to improve the assimilative powers well, and, like geum, myrica, and a few other agents, to give firmness and activity to lax mesenteries in scrofulous constitutions. Certain it is that, in curdy diarrhea, cholera morbus, and similar difficulties, its action in diminishing the discharges and giving tone to the duodenum, small intestines, and possibly the pancreas, is most favorable.

The average cathartic dose for an adult, is about thirty grains. The alkalies, by acting upon the acid principle of the root, increase its cathartic power; so that fifteen grains of the root, in company with three to five grains of bicarbonate of soda or potassa, usually make an efficient evacuant. Heat, on the other hand, drives off a portion of volatile material in which the cathartic power seems to reside; so that roasted rhubarb is more distinctly astringent than the common root. For bilious diarrhea three grains of rhubarb may be given with two grains bicarbonate of soda, and two grains fresh charcoal, (especially that made from corks,) and repeated every three or four hours, to much advantage. Two grains of rhubarb and one grain of leptandrin, will be found of much service in diarrhea, dysentery, typhoid looseness of the bowels, etc. Though not partial to the use of camphor, I have found much advantage in moistening five grains of this gum with a few drops of alcohol, rubbing it with ten grains of bicarbonate of soda and thirty grains of rhubarb, and giving five grains of this mixture every three hours, till the passages become yellow, in cholera morbus, diarrhea, dysentery, and cholera.

Pharmaceutical Preparations: I. Extract. This is obtained by treating a pound of crushed rhubarb in the percolator with diluted alcohol till a gallon has passed, and carefully evaporating this to the proper consistence on the water bath. Heat readily injures it, and much of this extract on the market is of trifling value. A good article has the smell and taste of the root strongly marked, and may be used in cathartic doses of ten grains.

II. Fluid Extract. A pound of rhubarb is to be crushed mixed with a pound of sand, moistened with seventy-five percent alcohol, and treated by percolation till six fluid ounces have passed; reserving this, continuing the percolation with diluted alcohol till two pints have passed, evaporating the latter product to ten fluid ounces, and mixing the two products. Or half a pound of sugar may be added to the second product, and it then evaporated to ten fluid ounces, and mixed with the first product. Laxative dose, twenty to forty drops.

III. Pills. Six drachms of powdered rhubarb are to be beaten well in a mortar with the shavings of two drachms of soap. (White Castile soap is always preferable.) Use a sufficient quantity of water to form a pill mass, and make into one hundred and twenty pills. (U. S. P.) Each pill contains three grains; and they may be used as a mild laxative.

IV. Compound Pills. Rhubarb, one ounce; aloes, six drachms; myrrh, half an ounce; oil of peppermint, half a fluid drachm. Beat with water into a proper mass, and divide into two hundred and forty pills. (U. S. P.) These are stimulating laxatives, in which the aloes counteract the rhubarb, and the quantity of peppermint oil is unpleasantly excessive. A far better hepatic tonic formula is the following:

V. Rhubarb and Leptandrin Pills. Rhubarb, one ounce; leptandrin, two drachms; hydrastis, one drachm. Beat, in a mortar, two drachms of white castile soap and fifteen drops oil of caraway; mix the powder well with these; and then add a sufficient quantity of molasses to form a pill mass. Divide into four-grain pills. These act mildly on the liver, gall-ducts, and bowels, and leave a gentle astringed and tonic impression; and are of much value in diarrhea, dysentery, light biliousness, and similar cases. I offer them to the profession as a preparation of good qualities.

VI. Sirup. Mix four ounces of crushed rhubarb with eight ounces of sand, and add four ounces of thirty-five percent alcohol. After four hours, transfer to a percolator, and add alcohol of the same strength till two quarts (in all) have been used. Evaporate on a water bath to thirteen fluid ounces, and form into a sirup with two pounds of sugar. A mild laxative for infants, in doses of one to two fluid drachms. Rhubarb swells largely when wetted, and will form so compact a mass that sand (or coarser drugs) must always be incorporated with it when treated by percolation.

VII. Aromatic Sirup. Rhubarb, two ounces and a half; cloves, cinnamon, and ginger, each half an ounce. Macerate the crushed articles for four hours in a sufficient quantity of diluted alcohol, transfer to a percolator, and treat with diluted alcohol till two pints have passed, evaporate this to a pint on a water bath, and add it to six pints of heated simple sirup. Or the articles may be tinctured for fourteen days with a quart of diluted alcohol, strained, evaporated to a pint, and then added to the warmed sirup. The U. S. P. uses two drachms of nutmegs instead of the above half ounce of ginger. It is a mild aromatic laxative for children in doses of a fluid drachm every two hours till the passages look yellow. Twenty grains of bicarbonate of potassa may be added to each eight ounces of the sirup, when an alkaline accompaniment is desirable.

VIII. Compound Powder, Rhubarb and Magnesia. Mix well together the powders of four ounces rhubarb, two ounces ginger, and one pound calcined magnesia. The quantity of magnesia, in practice, is seldom greater than six ounces. It is a mild antacid and laxative, of much value for children and lying-in women. Dose for an adult, half a drachm to a drachm; for a child of three years, ten grains or less.

IX. Tincture. Rhubarb, three ounces; cardamon seeds, half an ounce. Crush well, macerate for fourteen days with a quart of diluted alcohol, express, and filter; or treat by percolation after forty-eight hours of maceration in a sufficient quantity of the diluted alcohol. Two drachms of coriander seeds make the preparation pleasanter. It is seldom used alone, but is a good cordial adjunct to stronger purgative mixtures. Dose, as a stomachic, a fluid drachm; as a laxative, half a fluid ounce. It is. suitably combined with infusion or sirup of gentian in very lax and atonic conditions.

X. Sirup of Rhubarb and Potassa, Neutralizing Cordial. Rhubarb, well crushed, four ounces; dried peppermint herb, eight ounces, (or the green herb, four ounces;) golden seal and cinnamon, each, one ounce. Macerate for two days with one quart of brandy, or with the same quantity of forty percent alcohol. Transfer to a percolator, treat with water, and set aside the first pint and a half. Continue the process with water till three quarts have passed, express the dregs, add four pounds of sugar, and dissolve at a gentle heat–evaporating till the addition of the first liquid shall make a gallon. When cold, mix the liquors, and add one ounce and a half of the bicarbonate (not carbonate) of potassa. The addition of the alkali turns the whole sirup deep red, and occasions a flocculent precipitate, to remove which, the whole may afterward be filtered through flannel; though in practice this sediment may be allowed to remain, and shaken up when used, as it contains no inconsiderable portion of power, though not so palatable as many desire. Two ounces of bicarbonate of soda may be used in lieu of the potassa alkali, but the latter is preferable. Some formulas use as much alkali as rhubarb; but this makes an unduly alkaline preparation, and one not sufficiently medicinal. When desired, or when the presence of liquor is objectionable, the ingredients may be mixed in powdered form, and made into infusion as needed. Some prefer to add twenty drops of peppermint oil and ten drops of cinnamon oil, by trituration, to each gallon of the sirup, instead of percolating the drugs; but percolation makes a better article. Merrell and some others tincture the drugs on seventy-six percent alcohol; but such a preparation is unfit to use.

Dr. H. H. Hill prepares this sirup with two ounces, each, rhubarb and carbonate potassa; one ounce each golden seal and cinnamon, treating them with a gallon of brandy, and adding four pounds of sugar and twenty drops oil of peppermint. This is very pleasant to the taste; but the small quantity of rhubarb, and large quantity of potassa, make it less medicinal than the sirup obtained by the above formula.

This sirup is based upon an ancient German formula, which directed two parts of Turkey rhubarb, and one part each of peppermint and bicarbonate of soda. Dr. W. Beach first gave it prominence in American practice, but failed to give credit for its origin. It is unsurpassed for flatulent and bilious diarrhea, dysentery, flatulent pains in the bowels, the green and griping discharges of children, sourness with feebleness of the stomach, etc. The dose may range from a drachm to an ounce, at intervals of six hours or less. It is very soothing to young children, to whom it may be given in doses of ten drops to a teaspoonful. If the discharges are watery, one-tenth part of tincture of myrrh may be combined with it; and if there is hepatic obstruction, an equal part of fluid extract of leptandra may be used with it, till the liver is acted on. I have found much advantage, in severe flatulence, in adding from one-fourth to one-half a part of fluid extract of dioscorea to this sirup; or a small proportion of fluid extract of valerian and essence of anise may be employed in griping diarrhea, restlessness, and a tendency to convulsions, in children.

The Physiomedical Dispensatory, 1869, was written by William Cook, M.D.
It was scanned by Paul Bergner at http://medherb.com