BACKGROUND
Heliopsis longipes (A. Gray) Blake (Asteraceae) is a broadly used species in the Mexican, Central and South American Traditional Medicine for its anaesthetic, analgesic, anti-inflammatory and anti-ulcerative properties. The ethanolic extract contains alkamides, mainly affinin
Heliopsis longipes roots have been widely used in Mexican traditional medicine to relieve pain, mainly, toothaches. Previous studies have shown that affinin, the major alkamide of these roots, induces potent antinociceptive and anti-inflammatory activities. However, the effect of H. longipes root