[Significance of topical therapy in clinical situations. Location-dependent principles]

Topical therapy remains an important domain of dermatology. The choice of the base or vehicle for topical therapy has to be appropriate for both the skin disorder and the localization. In cases with intact skin barrier (horny layer, lipid barrier) lipophilic formulations are more suitable because of superior penetration, whereas hydrophilic creams should be favored when facing more acute, weeping skin conditions. Because of location-specific variations in the macro- and micro-anatomy and the microbiota of the skin, the topical agent that is chosen must have quite specific properties in order to function optimally. These location-specific differences and potential therapeutic principles will be discussed in greater detail.