Amentoflavone (3',8''-Biapigenin), as a potent inhibitor of CYP3A4 and CYP2C9, can interact with many other medications. CYP3A4 and CYP2C9 are proteins used for drug metabolism in the body. Amentoflavone also is an inhibitor of human cathepsin B. It has antimalarial activity in trials significant affinities towards the Delta-1, kappa opioid receptors (as an antagonist) and binds to benzodiazepine receptors. Amentoflavone may be a potential lead for a new type of anti-inflammatory agents having the dual inhibitory activity of group II phospholipase A2 and cyclooxygenase. Amentoflavone and quercetin differentially exerted suppression of PGE2 biosynthesis via downregulation of COX-2/iNOS expression.