COLCHICUM
The poisonous properties of Colchicum autumnale, Meadow Saffron (N.O. Melanthaceæ) reside in an alkaloid Colchicine, chiefly found in the corms, but also present in other parts of the plant. The seeds have caused death.
In June 1875 an epidemic of gastric irritation among the inhabitants of Rione Boego was traced to the use of the milk of goats which had accidentally eaten the leaves of colchicum.
Symptoms.—Colchicum, in medicinal doses, increases the activity of the liver, and bile is freely secreted. The action of the kidneys and of the skin is also increased. The heart is more or less affected, and its frequency diminished. In large doses, all the symptoms of irritant poisoning are present, and in some cases have been likened to those observed in Asiatic cholera.
Post-mortem Appearances.—Death may result from its use without leaving any morbid appearances. In other cases, however, the usual signs of inflammation were present. Casper describes the colour and condition of the blood in those poisoned by colchicum as dark cherry-red, with the consistency of treacle. A marked congestion of the vena cava may also be present.
Chemical Analysis.—Colchicine, obtained by Stas process, added to concentrated nitric acid, becomes of a violet colour, changing to blue and brown. The violet solution changes to yellow on dilution with water, then to red on adding caustic soda. Tincture of iodine precipitates colchicine of a kermes brown colour, platinum bichloride yellow, and tannic acid white, the precipitate being soluble in alcohol, acetic acid, and alkaline carbonates. Strong sulphuric acid gives a yellow colour with colchicine, which changes to green, violet, and reddish-brown on the addition of nitric acid.
Fatal Dose.—One ounce of the tincture.
Treatment.—Stimulants and opium should be given to counteract its depressing effects. Tannin is said to be an antidote.