Nux vomica is derived from the seeds of a plant that grows in India. Strychnin is the alkaloid which exists therein. Strychnin is quite different in its effects from the above-mentioned alkaloids, for instead of benumbing the nerves, causing sleep or a pleasing sensation, the effect is a nerve stimulus which causes muscular convulsions.

The medical use of strychnin is more of a stimulant than of a narcotic. It is given only in desperate cases where there is some hope that the convulsive effect of the drug may cause the patient to revive. This treatment, however, is very questionable, and is not practised by many of the ablest authorities on drugs.