Chapter 4. Moisturization
Regular moisturizer therapy can help to re-establish and preserve the stratum corneum barrier. Emollients can hydrate the skin, reduce susceptibility to irritants, decrease pruritus and decrease inflammation. Adding a moisturizer to a low potency topical corticosteroid has been shown to improve clinical parameters and decrease the need for topical corticosteroids
Moisturizers are available in ointments, creams, lotions and oils. In general, ointments have the fewest additives and are the most occlusive. They are generally well tolerated. However, in a hot, humid environment, they can trap perspiration, resulting in increased pruritus or sterile folliculitis. Creams and lotions have a higher percentage of water than ointments, making them easier to rub on than ointments. However, lotions and creams can be irritating due to added preservatives or fragrances. In addition, the higher water content of lotions can have a drying effect on the skin due to evaporation. While oils are easy to apply, they are often less effective than ointments or creams.
Liberal use of moisturizers in large quantities and with frequent application should be encouraged, and caregivers should know that some moisturizers are available in one pound jars. Petrolatum or vegetable shortening can be used as inexpensive moisturizers. Moisturizers applied directly over topical medications can dilute out the medication; optimally moisturizers should place on the skin at least twenty minutes after topical prescriptives. Rarely, contact dermatitis can develop to moisturizers. For example, some atopic dermatitis patients may become sensitized to lanolin, and may develop contact allergy when moisturizers with this ingredient are used.
Since a number of studies suggest that atopic dermatitis is associated with decreased levels of ceramides, contributing not only to a damaged permeability barrier, but also making the stratum corneum susceptible to colonization by S. aureus, use of a ceramide-dominant emollient has been proposed. While a ceramide-dominant cream has been marketed as a barrier repair cream (Triceram®), it has only been studied in an open add-on fashion without appropriate controls and is significantly more expensive than most moisturizers.
Alpha-hydroxy acids such as 12% ammonium lactate have been shown to have beneficial effects on the skin including improvement of the skin barrier function. Of potential importance, 12% ammonium lactate has been shown to mitigate atrophic changes associated with use of topical corticosteroids. However, ammonium lactate should not be applied to open lesions as this may cause significant burning and stinging.