Modified-release topical hydrogels: a ten-year review

Abstract

Hydrogels are polymeric networks with tridimensional structure, which are able to load water and other substances. Such property makes hydrogels suitable for innumerous applications in biomedical field. Hydrogels are being used as raw materials in pharmaceutical formulations for more than 60 years, while significant progress is very well documented in topical use. Natural and synthetic polymers have been applied to develop smart hydrogels that respond to physiological stimuli to follow the release of the loaded bioactive ingredient. This paper discusses the most relevant polymers commonly used in pharmaceutical formulations for modified topical delivery.