Strychnine is a highly toxic alkaloid derived from the seeds of the Strychnos nux-vomica tree, native to Southeast Asia and Australia. It is primarily known for its use as a pesticide, particularly for controlling rodents. Strychnine affects the nervous system, leading to severe muscle spasms and convulsions, and can be fatal in small doses. In addition to its toxic properties, strychnine has been studied for its potential effects on the human body. Historically, it was used in small amounts as a stimulant and in some traditional medicines. However, due to its dangerous nature, its use is now heavily regulated in many countries.