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 .
Even though topical corticosteroids such as creams or ointments are applied to the surface of the skin, they can still cause side effects . Long-term use or excessive use can lead to thinning of the skin, irritation, dryness, or changes in skin color. If your doctor recommends that you occlude your psoriasis areas -- wrapping them in plastic after applying a topical corticosteroid to boost the effect -- side effects may be more common. More serious side effects may occur with topical corticosteroids if used in high doses for prolonged periods. You may become resistant to the helpful effects of topical corticosteroids over time, too.
It is important to use the correct amount of topical steroid for your eczema, as instructed by your healthcare professional. Topical steroids should be applied with clean hands so that the skin just glistens. It can sometimes be difficult to judge how much steroid to use and there are guidelines on the amount required to cover body areas that are affected by eczema. These are based on the Finger Tip Unit (FTU), and explained in detail in our fact sheet which you can download as a pdf from the related documents to the right of this page.