The British Pharmacopoeia contains (i) an extract of the fresh corm, having doses of 4 to i grain, and (2) the Vinum Colchici, made by treating the dried corm with sherry and given in doses of 10 to 30 minims. This latter is the preparation still most generally used, though the presence of veratrine both in the corm and the seeds renders the use of colchicine itself theoretically preferable.
When inhaled, the powder causes violent sneezing, similar to that produced by veratrine itself, which is, as already stated, a constituent of the corm.
This is accelerated by a marked depressant action upon the heart, similar to that produced by veratrine and aconite.
Veratrine is useless in the treatment of gout.
Immediately before arrest the heart may beat much faster than normally, though with extreme irregularity, and in the lower animals the auricles may be observed occasionally to miss a beat, as in poisoning by veratrine and colchicum.
(3) Quinoline group. The alkaloids of the quina-barks: quinine, &c.; the strychnos bases: strychnine, brucine; and the veratrum alkaloids: veratrine, cevadine, &c.
The chief constituents of colchicum are two alkaloids, colchicine and veratrine.