COPAIBA. — "Balsam" copaiba, or copaiva, is the common designation of this drug, but is exceedingly inappro priate, since it contains neither of the requisites of a true balsam, viz.: benzoic or cinnamic acid. It is, in fact, an oleo resin supposed to be derived from Co paifera Langsdorffii, but as frequently, perhaps, had from other, but relative, sources, such as C. officinalis, C. multi juga, C. Guianensis, C. coriacea, C. nitida, C. Martii, C. cordifolia, C. Jus sieui, C. Jacquini, etc., all indigenous to South America or the West Indies and the valleys of the Madeira, Orinoco, and Amazon; the best comes from Belem (Para), as its average of volatile oil is larger, ranging from 60 to 90 per cent., while its most important rival, Maran ham copaiba, at most never yields more than 80 per cent. and seldom more than 40, which last equals that of Maracaibo.
Para copaiba is pale colored and limpid, Maranham and Rio Janeiro of an olive-oil consistence, and all three form clear mixtures with one-third to one-half their volume of ammonia-water, but milky if more alkali or fixed oil is present. Maracaibo—and all dark co paibas obtain this name commercially— is thick, dark yellow or reddish brown, turbid, and solidifies with magnesia. Besides the volatile oil is contained a resin and bitter principle known as co paivic acid: oxycopaivic acid from the Para form, metacopaivic acid from that dubbed Maracaibo. The odor is peculiar and characteristic; the taste, hot, nause ous, and bitter; is freely soluble in ether, alcohol, fixed and volatile oils, but not at all in water unless it is previously rendered alkaline.
Copaiba-oil is obtained by distillation, and in this the therapeutic virtues of the oleoresin chiefly reside. Tt is a pale yellowish liquid; aromatic; bitter, pun gent taste and characteristic odor; that from Maracaibo copaiba has a dark-blue tinge.
Unfortunately copaiba is rarely ob tained in its purity; that in the shops is usually adulterated with turpentine, gur jun balsam, or castor- or linseed- oils.
Preparations and Doses. —Copa ib a (oleoresin), 5 to 15 grains or minims.
Copaiba injection, urethral (copaiba, 10; sodium bicarbonate, 5; tincture of opium, 1; distilled water, to make 768 parts), ad libitum.
Copaiba mass (solidified copaiba, 10 to 60 grains) speedily becomes insoluble.
Copaiba mixture (copaiba, 6; liquor potassa, 4; gum-arabic mucilage, 8; spirit of nitrous ether, 24; cinnamon water, 64), 2 to 5 drachms and more.
Copaiba mixture, Chopart-AVolff's (co paiba, 8; syrup of Tolu, 8; alcohol, 8; spirit of nitrous ether, 1), 2 to 5 drachms.
Copaiba-oil 3 to 15 minims.
It may here be noted the custom of making pills of copaiba by the aid of magnesia carbonate, and by mixing with wax, is pernicious; neither pill-mass is freely soluble, and absorption of the remedy is restricted and in a measure inhibited.
Physiological Action. — Applied lo cally both the oil and the oleoresin ap pear to be slightly stimulant. Internally in medicinal doses they stimulate the kidneys to freer action, without, how ever, materially affecting or modifying the solid constituents of the urine.
The diuretic action is produced by the effect of the drug upon the renal secre tory nerves, and not by dilatation of the blood-vessels of the kidneys, as believed by Binz. Obelensky (Brit. Med. Jour., Aug. S, '91).
When copaiba is taken normally, a re ducing substance appears in the urine, which responds to Trommer's test, but not to Nylander's or the fermentation test, and deflects polarized light to the left. This levorotatory substance be longs to the paired glycuronic acids, and may easily be mistaken for sugar, the more so as free glycuronic acid is dextro rotatory like glucose. But glycuronic acid is not fermentable with yeast. Bett man (Berliner klin. Woch., May 29, '99).
Copaiba stimulates mucous membrane generally, more especially of the genito urinary and respiratory tracts; is some what feebly astringent, and decidedly antiseptic. Its prolonged use is not un attended with danger and is apt to in duce considerable gastro-intestinal tation, gastric oppression, anorexia, nausea, vomiting, purging, and con gestion of the upper air-passages, of the conjunctiva, irritation of bladder and kidneys, perhaps to the setting up of a nephritis or cystitis, or both. Unpleas ant skin eruptions accompanied by in ordinate itching and tingling are com mon sequels to its use; usually these consist of bright-red papules closely re sembling the efflorescence of measles, but sometimes scarlatina-like. They begin on the hands, gradually spreading to arms, trunk, and lower extremities.