Dynamic foams in topical drug delivery
Objectives: Pharmaceutical foams are not new inventions and their application in topical therapy can be traced back three decades. However, foam formulations have been gaining in popularity with over 100 patents published globally in the last 10 years alone. The aim of this paper is to review the current status and explore the future potential of dynamic foam vehicles in the field of topical drug delivery. Key findings: The use of foam technology to deliver a range of topical active agents has been claimed, including sun-screening compounds, corticosteroids, and antibacterial, antifungal and antiviral agents. Although foams present distinct application advantages and improved patient compliance, the real reason for the rapid growth of topical foam technology is that foams as elegant, aesthetic and cosmetically appealing vehicles provide an alternative, promising formulation strategy in the highly competitive dermatological market. Although there is a plethora of published data proving the safety profiles of topical foams there is a lack of sufficient clinical evidence to demonstrate any superiority of foams over other traditional topical vehicles such as creams and ointments for drug delivery. Summary: Recent literature suggests that when foams are properly engineered using the advances of in situ analysis techniques, the enhancement of topical drug delivery via engineering this type of vehicle can be achieved.