[Lipid vehicles for the parenteral administration of drugs (2): liposomes]

The studies conducted in the past decades of the different medication carriers, have made different active substances available to the therapeutic arsenal, by using liposomes as a vehicle. Since Bangham discovered their preparation in the sixties, important technological advances have taken place on this formulation, with there being great expectations for its potential application as a vehicle for medication or other active molecules. The presently available knowledge in preclinical and clinical studies with different liposomal formulations of narrow range active substances with a high toxicity, have allowed them to be objectively seem as a good administration system for these drugs, since their more selective action improves their tolerance. Nevertheless, there are problems with regard to the implementation of their use, which in general we could summarize as its chemical instability, difficulty in manufacturing, and high cost of technology. In the present study, the physical and chemical characteristics, the properties and the formulations of the liposomes are reviewed, as well as the results of studies published with reference to the efficacy and the therapeutic applications, mainly in the area of chemotherapy and anti-infectious therapy.