Condurango is the bark of Gonolobus Cundurango, Triana (N.O. Asclepiadeae), a climbing plant indigenous to Ecuador. The bark is removed from the stem by beating with a mallet, and then dried in the sun. The bark occurs in quilled or curved pieces about 5 to 10 centimetres long, 0.5 to 2.0 centimetres wide, and 2 to 6 millimetres thick. It is covered externally with a thin greyish-brown cork, which is often warty, sometimes scaly; the inner surface is paler and coarsely striated. It breaks with a short, somewhat fibrous fracture. The section is pale and, when examined under the lens, exhibits scattered groups of sclerenchymatous cells. Under the microscope it is characterised by the abundance of cluster crystals of calcium oxalate, numerous laticiferous vessels and groups of stone cells and bast fibres. The bark is almost odourless, but has a bitter and somewhat acrid taste.
Constituents.—The active constituents of Condurango are but imperfectly known. It contains a toxic resin, and one or more glucosides varying in their toxicity, condurangin being the name applied to a mixture of such glucosides. Condurangin, or that constituent of it which is soluble in cold water and is the most toxic, possesses the remarkable property of coagulating like albumin when its aqueous solutions are boiled, the coagulum being redissolved on cooling. Hence decoctions of condurango should be strained when cold, otherwise the whole of the condurangin may be removed. Condurangin has been considered to be identical with vincetoxin.
Action and Uses.—Condurango is a bitter substance used in dyspepsia. It was introduced as a cure for cancer, but has no effect on the progress of that disease. A liquid extract is prepared, and condurango wine is a favourite Continental form of the drug.
Dose.—1 to 4 grammes (15 to 60 grains).
- Extractum Condurango Liquidum, B.P.C.—LIQUID EXTRACT OF CONDURANGO. 1 in 1.
- Often prescribed in mixtures with other alteratives such as potassium iodide and perchloride of mercury. For its gastric sedative action it may be mixed with bitters and taken half an hour before a meal. Dose.—1/2 to 4 mils (10 to 60 minims).
- Vinum Condurango, B.P.C.—CONDURANGO WINE. 1 (liquid extract) in 10.
- Introduced as a cancer cure, and wonderful results were at first reported, as with all such "cures." It is no longer used in cancer, but is given to a small extent as a gastric sedative. Dose.—15 to 30 mils (1/2 to 1 fluid ounce).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.