Leukotriene C4 is a pro-inflammatory cysteinyl leukotriene derived from arachidonic acid and produced from leukocytes in response to inflammation. It is one of the constituents of slow-reacting substance of anaphylaxis (SRS-A), and is a potent agonist for the contraction of smooth muscle. Contributes to the pathogenesis of asthma and acute allergic hypersensitivity through bronchoconstriction and vascular permeability.