Desonide (Desonide Topical) - Description and Clinical Pharmacology

For Dermatological Use Only - Not for Ophthalmic Use      Rx Only

Description

Desonide Ointment contains desonide (Pregna-1,4-diene-3,20-dione,11,21-dihydroxy-16, 17-[(1-methylethylidene)bis(oxy)]-, (11β,16 α)) a synthetic corticosteroid for topical dermatologic use. The corticosteroids constitute a class of primary synthetic steroids used topically as anti-inflammatory and antipruritic agents.

Chemically, desonide, the active ingredient in Desonide Ointment, is C₂₄H₃₂O₆. It has the following structural formula:

Desonide has the molecular weight of 416.51. It is a white to off-white powder. The solubility of desonide in distilled water saturated with ether is 184 mg/L.

Each gram of Desonide Ointment contains 0.5 milligrams of desonide microdispersed in a base of white petrolatum.

CLINICAL PHARMACOLOGY

Like other topical corticosteroids, desonide 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 A₂ 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 A₂.

Pharmacokinetics

The extent of percutaneous absorption of topical corticosteroids is determined by many factors including the vehicle and the integrity, of the epidermal barrier. Occlusive dressings with hydrocortisone for up to 24 hours have not been demonstrated to increase penetration; however, occlusion of hydrocortisone for 96 hours markedly enhances penetration. Topical corticosteroids can be absorbed from normal intact skin. Inflammation and/or other disease processes in the skin may increase percutaneous absorption.

Studies performed with Desonide Ointment indicate that it is in the low range of potency as compared with other topical corticosteroids.