retentine- it is a species of herbaceous plant, annual, of the family Asteraceae, about 70 cm high, very toxic, considered a weed, native to South America; it has opposite leaves, small pink or white flowers of nauseating smell, becoming a weed of the tropical areas of the world-It is used medicinally as an antibacterial or antiarthritic, also, for its essential oils, it is used in cosmetics; is toxic to mammals-