[Transdermal therapeutic systems for drug administration].

Transdermal therapeutic systems, or transdermal patches, facilitate controlled release of active ingredients through the skin and into the systemic circulation. Drugs administered through such systems escape first pass metabolism and steady state is maintained similar to a continuous intravenous infusion for up to several days. Few pharmacologically active substances can currently be administered through transdermal patches and production is technically demanding. Research is ongoing to improve the systems and expand the indications. This article gives a brief overview over principles behind various transdermal patch types, as well as the advantages and disadvantages of transdermal therapeutic systems.