Among various approaches to intra- and percutaneous administration of drugs, e.g. application of patches, ointments, iontophoresis, electroporation, the use of lipid vesicles like liposomes and niosomes presents numerous advantages. They are not toxic or invasive, may deliver hydrophobic and/or hydrophilic molecules, and the size of the transported molecule is not a limiting factor. Liposomes are obtained with natural amphiphilic lipids whereas niosomes are composed of synthetic amphiphilic molecules. These microscopic vesicles contain from one to several concentric lipid bi-layers with intercalated aqueous compartments. Trans-epidermal penetration of the vesicles is proportional to the "fluidity" of their lipids and their negative charge. Several drugs and cosmetics in this gallenic form are already commercially available and successfully used, presenting a better dose/effect ratio and provoking less side-effects. (C) 2003 Editions scientifiques et medicales Elsevier SAS. Tous droits reserves.
