This section is from the book "A Text-Book Of Pharmacology, Therapeutics And Materia Medica", by T. Lauder Brunton. Also available from Amazon: A text-book of pharmacology, therapeutics and materia medica.
The rhizome and rootlets of Veratrum viride. United States and Canada.
Characters. - Rhizome two or three inches long, one to two inches thick, with numerous shrivelled, light yellowish-brown rootlets.
Composition. - It contains several alkaloids - jervine, pseudo-jervine, cevadine, very little rubijervine, and traces of vera-trine and veratralbine. Veratroidine, which was formerly regarded as one of its constituents, is probably rubijervine and resin.
Dose. - Of the powdered rhizome, 1-3 gr. or more.
Tinctura Veratri Viridis.............................................................
5-20 min. or more.
Extractum Veratri Viridis Fluidum...............................................
Tinctura ,, ,, ...........................................................
Action. - In small doses veratrum viride lessens the strength of the pulse in man without at first affecting its rate, but afterwards it renders it very slow, soft, and compressible, although sometimes moderately full. At this stage any exertion at once renders the slow pulse rapid, feeble, small, and even imperceptible. The depression of the circulation is accompanied by muscular weakness, and frequently, though not always by nausea and vomiting. When the dose is large these symptoms become increased, and a state of collapse comes on with an exceedingly rapid, almost imperceptible pulse, cold clammy skin, constant nausea and retching, intense muscular weakness, giddiness, loss of vision, and partial unconsciousness.
The action of veratrum viride is due to the jervine and other alkaloids which it contains. It has been mentioned already that veratroidine is not a pure alkaloid, but as no further investigations have been made on the alkaloids of veratrum since those of Professor H. C. Wood, I give his results.
Jervine lessens the functions of the spinal cord, both in frogs and mammals, and of the medulla (especially the vasomotor centre), and of the cardiac ganglia, and at the same time irritates the motor centres in the brain, producing convulsions. Thus the symptoms produced are muscular weakness, loss of reflex action, followed by tremors, lowered blood-pressure, and slow pulse.
Respiration ceases before the heart, and death ensues from asphyxia. There is invariably salivation, but no vomiting nor purging. It has no action on the vagus, and the slow pulse is due to an action on the cardiac muscle or its ganglia. Voluntary muscles and motor nerves are little, if at all, affected by it.
Veratroidine differs from jervine in always causing vomiting and purging, and in producing less violent convulsions. It stimulates the vagus centre and paralyses the vagus ends. It depresses the spinal cord and paralyses the respiratory centre, but increases the excitability of the vaso-motor centre. At first it slows the pulse and lowers the blood-pressure. Next the pulsations become very powerful, though still slow, and the blood-pressure rises to normal. Then the pulse becomes very rapid, and the pressure rises greatly. This rise is, however, not due to the direct action of the drug, but to stimulation of the vaso-motor centre by asphyxial blood from paralysis of the respiration. If artificial respiration be kept up veratroidine steadily lessens both pulse-rate and blood-pressure.
Uses. - Veratrum viride has been used as a cardiac depressant in inflammations, but has not come into general use.