ABSTRACT:
Microemulsions are clear, stable, mixtures to immiscible phases. It contains Smix (surfactant: Cosurfactant), Oil, Water phase, with droplet sizes typically ranging from 10 to 100 nm. Microemulsions act as potential drug carrier systems for oral, topical, parenteral, Nasal & Preantral administration. In recent years, microemulsion-based drug delivery systems have gained significant attention due to their ability to enhance solubility, stability, and bioavailability of both hydrophilic and lipophilic drugs. This review provides a comprehensive overview of microemulsions, including their definition, historical development, components, classification, and physicochemical characteristics. The differences between macroemulsions and microemulsions, types of microemulsion systems (o/w, w/o, and bicontinuous), and Winsor phase behaviour are discussed in detail. Furthermore, the advantages and limitations of microemulsions as drug delivery vehicles are critically evaluated. Special emphasis is placed on their pharmaceutical applications, including topical, nasal, ocular, vaginal, and oral delivery systems. the relevance of microemulsion-based delivery systems in the management of periodontal diseases, particularly periodontitis, is discussed, considering their potential to enhance local drug concentration and therapeutic efficacy. Overall, this review underscores the promising role of microemulsions as versatile and effective carriers in modern drug delivery systems.