Pharmacology of Veratrum Californicum.

Abstract

Veratrum Californicum Durand has not been previously studied pharmacologically. Botanically, it is closely related to Veratrum viride and Veratrum album, although certain differences for identification purposes have been described by Viehover, Keenan and Clevenger, and Viehover and Clevenger. 1 The active constituents appear to be alkaloids similar to those of the other veratrums, but these have not been isolated as yet. A study of the drug appeared desirable because of suspected activity from reported poisonings, of its easy availability and abundant supply, which is not true of the other veratrums, and of the increasing interest in the therapeutic possibilities of veratrum for the circulation. Our supply was obtained at Cisco, California, 6000 feet elevation in the Sierra Nevada Mountains. Only the underground portion of the plant was found active. This was used as a 10 per cent tincture prepared from a No. 60 powder according to the Type Process P of the U. S. P. X, using 95 per cent alcohol as menstruum, and compared with a tincture similarly prepared from Veratrum album (Caesar and Loretz, Germany).

Results with dogs, rabbits, pigeons and frogs indicate that the actions of Veratrum Californicum are qualitatively identical with those of V. album, but quantitatively the drug appears less toxic, and intermediate between V. viride and V. album, the lower toxicity being in its favor for therapeutic purposes. The heart is slowed and the blood pressure lowered by small or therapeutic doses through central vagus stimulation, since the slowing does not occur after section of the vagi or atropine. After the second or third dose, the heart is greatly accelerated and the blood pressure raised, continued doses eventually causing collapse and death from direct cardiac depression and paralysis.