Ageratum conyzoides is an annual herb in the Asteraceae family with opposite ovate leaves and clusters of small flower heads. It is native to tropical Central and South America and has naturalised widely in warm regions, growing in fields and disturbed ground. In African traditional medicine it has been used as a febrifuge, to support wound care, and for conditions such as fever, colic, and skin ailments. Preparations often employ leaf and aerial parts, and phytochemical analyses show flavonoids, coumarins, terpenoids, and alkaloids. Some components display antioxidant and antimicrobial activity. The plant contains toxic pyrrolizidine alkaloids and requires careful control of formulation for safety.