8,11,14-Eicosatriynoic acid is an inhibitor of prostaglandin and leukotriene biosynthesis as well as arachidonic acid induced platelet aggregation. It inhibits cyclooxygenase (IC50 = 14 µM), human 12-lipoxygenase (IC50 = 0.46 µM), 5-lipoxygenase (IC50 = 25 µM) and the actions of slow-reacting substance of anaphylaxis (SRS-A) (IC50 = 10 µM).