How much of classical topical therapy is still current today? (author's transl)

Classical topical therapy has been largely displaced by the development of up-to-date drugs and advances in the galenic field. Serious objections have even been leveled against some older drugs and others are no longer current in spite of their good efficacy (e.g. dyes) because less discriminatory drugs can be substituted for them. The fundamental principles of classical topical therapy are still as valid as ever (inherent action of the base). However, many of the active principles of the prechemotherapeutic era have meanwhile been superseded as for example boric acid, mercury, desquamative pastes, sulfur among others. In contrast to this, topical applications such as dithranol, salicylic acid, coal tar and a few others still belong to the permanent stock of dermatological topical therapy.