Dermal

Abstract

Preparations for cutaneous (or dermal) application may be used for local treatment as well as for transdermal adminis- tration with a systemic effect. The chapter focuses on preparations with a local effect and on design of formulation andmethod of preparation of those prepared in pharmacies. The interaction between skin, active substance and base, the anatomy of the skin and biopharmaceutical aspects of cuta- neous preparations are discussed as well as the therapeutic effect of the base. Because of the important role of the pharmacist in prescription assessment some recommendations for the communication with the physician are given.One aspect ishowto proceedwith a request for the mixing of two licensed medicines or for the addition of an active substance or an excipient to a licensed product. The formulation design is generally following the several phases of the multicomponent preparations. Based on theclassification of the European Pharmacopoeia additionally the typical types of cutaneous dosage forms are discussed further, with regard to formulation as well as the way of processing. Extemporaneous preparation mostly involves the addition of active substances to base preparations. Preparations standardised in European formularies are used to illustrate special properties, design of formulation and preparation methods. Preparation processes for large scale require some othermethods than small scale preparations.