Origin

Gamboge is the concrete juice of a tree, growing in the Siamese province of Cambodia, and in Cochin China, and long since supposed to be a species of Garcinia, from the close resemblance of its product to that of one of the Garciniae of Ceylon, the Hebradendron Cambogioides of Graham. This supposition has been confirmed by recent researches, and it is now pretty well determined, through the agency chiefly of Dr. Christison, of Edinburgh, and Mr. Daniel Hanbury, of London, that the tree is a variety of the Garcinia Morella, of Ceylon, from which it differs mainly in having pedicelled instead of sessile flowers. When the leaves or young shoots of this tree are broken, a yellow opaque juice exudes, which is either received in hollow bamboo canes, where it is allowed to harden, or is collected in convenient receptacles, and, after attaining the proper consistence, is worked by the hand into rolls or other forms. Accordingly, it exists in commerce in two shapes, distinguished as the pipe, and the lump or cake gamboge. The former is in cylindrical rolls, separate or agglutinated together, sometimes bent on themselves, an inch or more in thickness and of variable length, often striated longitudinally on the outer surface, and more or less hollow within. The latter is in irregular masses, often filled with impurities, and generally of inferior value. The striated surface of the rolls is ascribed to the impressions from the inner surface of the bamboo, and the hollow in the centre to the shrinking during concretion.

Properties

The colour of the surface is a dull orange, diversified with greenish stains, and often concealed by the yellow powder produced by attrition. The broken surface is conchoidal, smooth, shining, and of a fine reddish-orange colour. The powder is of a beautiful bright yellow. Gamboge is without smell, and has little taste, but, when kept for a short time in the mouth, produces an acrid impression. it is inflammable. With water it forms a beautiful, bright-yellow, opaque emulsion. it is a gum-resin, consisting mainly of gummy and resinous matter, the former of which is soluble in water, the latter in alcohol or ether, and both in alkaline solutions. it is wholly dissolved, when treated successively by water and ether. The colour, acrimony, and medical virtues reside in the resinous ingredient, which constitutes a proportion of the whole, varying, in different specimens, from about 75 to 90 per cent. The resin is quite peculiar, and, having the acid property of neutralizing the alkalies, has received the name of gambogic acid.

Medical Properties and Uses

in full doses, gamboge is a powerful, drastic, hydragogue cathartic, producing very copious watery stools, and often operating with much harshness. it is very apt to cause nausea and vomiting; and its action is often attended with griping pains and general depression. its disposition to nauseate shows a special affinity for the upper portion of the alimentary canal, or rather a special susceptibility of this portion of the canal to its influence. Some ascribe this tendency to its ready solubility in the gastric liquor; but assuredly its active resinous matter is not more readily dissolved than the active matter of aloes, which water takes up, and which acts specially on the opposite extremity of the canal. in smaller doses, it is less disposed to irritate the stomach, while, if sufficiently often repeated, it still operates upon the bowels. The gum-resin is also thought to be diuretic.

In over-doses, it is capable of causing death by the conjoint gastrointestinal irritation or inflammation, and the great prostration from vomiting and hypercatharsis which it produces. Fatal effects have resulted from a drachm. Dr. Pereira ascribes the deaths which have ensued from the use of enormous quantities of Morrison's pills, mainly to the gamboge contained in them. in these cases, excessive vomiting and purging, pains and tenderness of the abdomen, a weak pulse and cold extremities have occurred during life, and signs of inflammation, ulceration, and gangrene of the intestines have been noticed after death. (3M. Med., 3d ed., p. 2027.)

Gamboge may be used whenever an energetic purgative effect is called for, and there is no irritability of the stomach present, and no reason to suspect inflammation of the bowels. But it is much more frequently given with other cathartics, to increase and hasten their action, than alone.

Dropsy is probably the disease in which it is most frequently specially employed. it is adapted to the treatment of this complaint by its powerful hydragogue operation, and its supposed diuretic powers. But caution should be observed in its use, lest it may aggravate any existing intestinal irritation on the one hand, or produce too great prostration on the other. it is peculiarly adapted to cases attended with great torpor of the bowels.

When strong revulsion is required from the head to the bowels, gamboge has been recommended; but its disposition to cause vomiting renders it, I think, of doubtful applicability to these cases.

In worms in the bowels it is often effectual, and has been employed successfully in the expulsion of the tapeworm. The use of it entered into Madame Nouffer's plan of treating the tapeworm, which was purchased by the King of France, and made public by his order.

Administration

The dose of gamboge is from two to six grains. in the treatment of tapeworm from ten to fifteen grains have been recommended. Generally, in order to avoid its nauseating and emetic action, it should be given in small doses of a grain or two every hour or two until it acts. in the treatment of dropsy, it is most advantageously used in conjunction with bitartrate of potassa, of which a drachm may be given with each grain of the gum-resin. The medicine may be administered in pill or emulsion, the latter form being preferable. it has been recommended in dropsical complaints, in the form of alkaline solution; and a tincture has been used on the Continent of Europe, as a powerful diuretic in these affections, made by digesting, for four days, half an ounce of gamboge and an ounce of carbonate of potassa, previously well rubbed together, in twelve ounces of brandy, and given in the dose of from thirty minims to a fluidrachm. Gamboge is an ingredient of the compound cathartic pills of the U. S. Pharmacopoeia, which may be properly noticed here, as this is the last of the cathartics I shall have occasion to describe, which enters into their composition.