Spreading of semisolid formulations: An update

Abstract

A considerable problem associated with the manufacture of topically applied pharmaceutical products is the establishment of reliable techniques for their characterization. the efficacy of a topical therapy depends on the patient spreading the ding formulation in an even layer to administer a standard dose. Spreadability is therefore an important characteristic of these formulations and is responsible for correct dosage transfer to the target site, ease of application on the substrate, extrudability from the package, and most important, consumer preference. This article discusses the various aspects of spreading, including the factors affecting it, the techniques available for its assessment, and various additives and interactions that can alter the spreadability of the final formulation.