ABSTRACT
As a result of their structure, multiple emulsions, i.e., emulsions of emulsions, can contain active water-soluble and lipid-soluble substances in each of the three constituent phases. Although potentially advantageous as systems for application to the skin and mucous membranes, multiple emulsions are not currently used as therapeutic dosage forms. This is due to the fact that such systems—investigated for only about ten years—are new vesicular forms that are still not fully controllable in terms of formulation, manufacture, characterization, and performance after application to skin or mucous membranes.
