Recent Update on Nanoemulsion Impregnated Hydrogel: a Gleam into the Revolutionary Strategy for Diffusion-Controlled Delivery of Therapeutics.

Since earlier times, dermatological remedies have been utilized to treat diseases associated with pain, irritation, and skin conditions. Compared to other routes of drug delivery, topical delivery of drugs offers several benefits. Scientists are investigating different alterations in dosage forms in addition to existing topical formulations such as ointments, gels, creams, lotions, and ointments to significantly improve the permeation of drugs and enhance the pharmacological efficacy of medications that are poorly absorbed via the skin. Conventional formulations have a plethora of problems viz. poor absorption, no target specificity, low spreadability, and inadequate bioavailability which leads the researchers toward developing novel formulations like nanoemulsions. The nanoemulsion can enhance the gradient in concentration and thermodynamic movement toward the epidermis and enhance the penetration of its constituents. However, due to its difficult application, nanoemulsion's lower viscosity limited its use in transdermal delivery. Thus, the development of nanoemulsion-based hydrogels has shown to be a successful strategy for removing obstacles from existing drug formulations. The simple application, expedient spreadability, non-stickiness, safety, and effectiveness of nanoemulsion-based hydrogel have led to substantial growth in their research in recent years. This review gives a brief idea about the prevalence of skin diseases, skin as an obstacle for drug delivery, and recent research insights to combat these obstacles. The work highlights the mechanism of drug release via nanoemulsion, hydrogels, and nanoemulsion-based hydrogels with reference to recent research on hydrophobic and hydrophilic drugs.