The most commonly used bases are ethyl alcohol, propylene glycol, polyethylene glycol, and water. Occlusive therapy is used in such conditions as psoriasis, atopic dermatitis, lupus erythematosus, and chronic hand dermatitis. Covering the treated area with a nonporous occlusive dressing increases the absorption and effectiveness of topical corticosteroids. Plastic tape impregnated with flurandrenolide is especially convenient for treating isolated or recalcitrant lesions. Aerosol forms of betamethasone dipropionate and triamcinolone acetonide are available but are seldom used because they offer no tangible advantage over creams, lotions, and solutions.
Soap is the most popular detergent, but synthetic detergents are also used.
However, acute irritated, weeping, or oozing lesions are most comfortably cleansed with only water or isotonic saline. Various ingredients often are added to detergents and other skin preparations to enhance or provide certain properties. For example, zinc pyrithione, selenium sulfide, or tar extracts may be added to shampoo for antidandruff action. Water is the principal solvent for cleansing. Powders dry macerated skin and reduce friction by absorbing moisture.