Transdermal and Topical Delivery of Anti-inflammatory Agents Using Nanoemulsion/Microemulsion: An Updated Review

Nanoemulsions/microemulsions are thermodynamically stable transparent (translucent) isotropic dispersions of oil and water stabilized by an interfacial film of surfactant and cosurfactant molecules having the droplet size of less than 100 nm. Because of their thermodynamic stability, they can be manufactured without utilizing high input of energy. In an attempt to enhance transdermal/topical drug delivery of anti-inflammatory agents (AIs), nanoemulsions/microemulsions have been more frequently employed over the recent years. Nanoemulsions/microemulsions have been shown to be superior for transdermal/topical delivery of particularly lipophilic compounds as compared to conventional vehicles such as emulsions, suspensions, gels and liposomes. Nanoemulsions/microemulsions exhibit excellent solubility properties. These vehicles also act as transdermal permeation enhancers without utilizing additional permeation enhancers. In this review transdermal and topical delivery of AIs both in vitro as well as in vivo has been summarized and reviewed.