An organic extract (PM-251) from a plant, Euphorbia hirta (Euphorbaceae) has been standardized. Agronomical standardization has been achieved on this plant by growing it in eastern North Carolina. Subsequently the PM 251 extract has been chemically and biologically standardized. The standardized extract has been tested for its efficacy as an anti-inflammatory product based on in vitro assays as well as in vivo (animal studies). The standardized extract has significant COX-2 (Cyclooxygenase) enzyme inhibition in vitro. PM-251 has proved to be a good anti-inflammatory agent in sub-acute rat models of inflammation in the doses of 100 mg/kbw, 200 mg/kbw and 400 mg/kbw body weights when given orally.