This section is from the book "Materia Medica Pharmacy, Pharmacology And Therapeutics", by W. Hale White. Also available from Amazon: Materia Medica Pharmacy, Pharmacology And Therapeutics..
Colchicum Root. The corm of Colchicum au-tumnale Linne (nat. ord. Liliaceae). Synonym. - Meadow Saffron.
Southern and Central Europe.
About 25 mm. long, ovoid, flattish and with a groove on one side; externally brownish and wrinkled; internally white and solid; often in transverse slices, reniform in shape, and breaking with a short, mealy fracture; inodorous; taste sweetish, bitter and somewhat acrid.
The chief constituents are - (1) Colchicine, C22H25No6, about 0.5 per cent., the active principle; a bitter alkaloid, usually amorphous, but may be obtained in prismatic crystals, soluble in water and Alcohol, and Chloroform, but changed by most acids into Colchiceine, C22H23No6. (2)
Incompatible. - All astringent preparations, tincture of iodine, and tincture of guaiacum.
Dose, 2 to 8 gr.; .12 to .50 gm., in powder.
Dose, 1/2 to 2 gr.; .03 to .12 gm.
2. Extractum Colchici Radicis Fluidum. - Fluid Extract of
Colchicum Root. By maceration and percolation with Alcohol and Water, and evaporation.
Dose, 2 to 8 m.; .12 to .50 c.c.
5. Vinum Colchici Radicis. - Wine of Colchicum Root. Colchicum Root, 400; by percolation with Alcohol, 150; and with White Wine to 1000.
Dose, 5 to 15 m.; .30 to 1.00 c.c.
The seed of Colchicum autumnale Linne (nat. ord. Liliaceae).
Subglobular, about 2 mm. thick, very slightly pointed at the hilum; reddish brown, finely pitted, internally whitish; very hard and tough; inodorous; taste bitter and somewhat acrid. Resembling Colchicum seed. - Black mustard seed (see p. 524.)
The chief constituents are - (1) The same as of the corm root, but the proportion of the active alkaloid Colchicine is smaller (0.3 per cent.). (2) A fixed oil, 6 to 8 per cent.
Dose, 1 to 5 gr.; .06 to .30 gm.
1. Extractum Colchici Seminis Fluidum. - Fluid Extract of Colchicum Seed. By maceration and percolation with Alcohol and Water, and evaporation.
Dose, 1 to 5 m.; .06 to .30 c.c.
a. Tinctura Colchici Seminis. - Tincture of Colchicum Seed. Colchicum Seed, 150; by maceration and percolation with Alcohol and Water to 1000.
Dose, 10 to 30 m.; .60 to 2.00 c.c.
3. Vinum Colchici Seminis. - Wine of Colchicum Seed. Colchicum Seed, 150; by maceration with Alcohol, 150; and with White Wine to 1000.
Dose, 10 to 30 m.; .60 to 2.00 c.c.
When applied to the skin colchicum acts as an irritant, causing hyperaemia and smarting, and the dust inhaled gives rise to sneezing.
Gastro-intestinal tract. - In moderate medicinal doses colchicum produces no effect on most persons beyond slightly increasing the secretion of bile, but with others it causes loss of appetite, and a little purging, nausea and colic. In larger doses it gives rise, in all persons, to great abdominal pain, vomiting and profuse diarrhoea with the passage of blood. It is in fact a powerful gastro-intestinal irritant. There is also great prostration, the pulse becomes small, rapid, and thready, the skin cold and bedewed with sweat, and the respiration slow; death is due to collapse. It is probable that these results are not, to any great extent, owing to the effect of colchicine on the heart or respiration, but that they are merely the consequence of the severe gastro-enteritis, which, it is well known, will cause fatal collapse. These effects are produced if colchicine is injected subcutaneously, a circumstance which shows that this alkaloid is an active principle of the drug, and that it is excreted into the intestine. It is a curious fact that after a certain point, increasing the quantity does not lead to an increase of the symptoms. In animals the action on the heart is not marked, but diarrhoea and vomiting are severe.
Nervous system. - Medicinal doses have no effect. Even a fatal dose does not impair consciousness. Cold-blooded animals bear much larger proportionate doses than warm, but in all, after large quantities, sensation is paralyzed, and ultimately the spinal motor centres are powerfully depressed, death taking place from respiratory paralysis. Colchicine is said to act on muscles like veratrine.
Kidney. - The most discordant statements have been made about the action of colchicum on the urine, but it has not been definitely shown that either the quantity or composition, even in the amount of uric acid, is altered. After death by poisoning, the alkaloid is found in the blood and in most of the organs of the body.