A Brief Review on Topical Gels as Drug Delivery System

The method of applying prescription dosage forms to the skin for direct treatment of a cutaneous disorder is known as a topical drug delivery system. Topical gels are semisolid dosage forms in which a liquid phase is constrained within a three-dimensional polymeric matrix derived from natural or semi-synthetic sources with high physical or chemical cross-linking. Because of their intermediate behavior between solid and liquid materials, topical gels are an excellent candidate for transdermal drug delivery. Clinical evidence indicates that topical gel is a safe and effective treatment choice for the management of skin-related diseases, especially when used for local action to avoid the side effects of other conventional dosage forms. Gels, cream, ointment, and paste are the most commonly used semi-solid formulations for topical drug delivery. Gels are colloids in which the liquid medium has thickened to the extent that it behaves like a solid. Since topical gel formulations are less greasy and can be quickly removed from the skin, they offer better drug delivery. In comparison to cream, ointment, and paste, gel formulations have improved application properties and consistency. This article aims to review the principles and recent developments in topical gels, including classification, methods of preparation, applications, and so on.