Strychnos is a genus of trees and shrubs belonging to the family Loganiaceae. These plants are primarily found in tropical regions, particularly in Africa, Asia, and South America. Some species produce seeds that contain strychnine, a potent alkaloid known for its toxic properties. The genus includes various species, some of which are used in traditional medicine, while others are considered harmful due to their toxicity. Strychnos nux-vomica, for example, is well-known for its seeds, which have been historically used in small doses for medicinal purposes but can be lethal in larger amounts.