The aqueous and methanol extracts of Achillea ageratum L. (Asteraceae) have been evaluated for analgesic, antipyretic and antiinflammatory properties in mice and rats in several experimental models. The aqueous extract exhibited significant activity in the analgesic and antiinflammatory assays but was unable to reduce hyperthermia. Moreover, the methanol extract exerted effects in three pharmacological actions. The phytochemical investigation of this latter extract revealed the presence of flavonic compounds: luteolin, quercetin and 7‐O‐β‐luteolin. © 1997 John Wiley & Sons, Ltd.