<p>Fluorometholone is thought to act by the induction of phospholipase A2 inhibitory proteins which control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of their common precursor arachidonic acid. On the other hand, Tetrahydrozoline is an alpha agonist which constricts the conjunctival blood vessels and thereby relieves the redness of the eye.</p>