Like other topical corticosteroids, hydrocortisone valerate has anti-inflammatory, antipruritic and vasoconstrictive properties. The mechanism of the anti-inflammatory activity of the topical steroids, in general, is unclear. However, corticosteroids are thought to act by the induction of phospholipase A 2 inhibitory proteins , collectively called lipocortins. It is postulated that these proteins control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes by inhibiting the release of their common precursor arachidonic acid. Arachidonic acid is released from membrane phospholipids by phospholipase A 2 .
Systemic corticosteroids can reactivate tuberculosis and should not be used in patients with a history of active tuberculosis, except when chemoprophylaxis is instituted concomitantly. The incidence or course of acute bacterial infection are probably minimally affected by inhaled triamcinolone. Application of topical corticosteroids to areas of infection, including tuberculosis of the skin, should be initiated or continued only if the appropriate antiinfective treatment is instituted. If the infection does not respond to the antimicrobial therapy, the concurrent use of the topical corticosteroid should be discontinued until the infection is controlled.