Herbal Hydrogels for Ophthalmic Drug Delivery in the Management of Dry Eye

Dry eye disease (DED) is a common and multifactorial disorder that adversely affects vision and quality of life. Conventional treatments, such as artificial tears and topical medications, are often limited by poor ocular bioavailability and rapid drug clearance. To overcome these barriers, herbal hydrogel systems have gained attention as innovative drug-delivery platforms. These hydrogels, prepared from natural polymers like hyaluronic acid and chitosan, combine excellent biocompatibility, high water retention, and tunable drug release with the therapeutic benefits of herbal extracts. By enhancing corneal permeability and prolonging ocular residence time, they provide both symptomatic relief and anti-inflammatory or antioxidative effects. Recent advances in smart hydrogels, including temperature-, pH-, and ion-responsive systems, further enable controlled drug release and extended contact with the ocular surface. In addition, applications such as hydrogel-laden contact lenses and biosensor-integrated hydrogels demonstrate their potential for both therapy and real-time monitoring. By mimicking the physiological tear-film environment, these systems enhance comfort, improve treatment efficacy, and may reduce dosing frequency. Future progress in polymer engineering, clinical trials, and clearer regulatory pathways will be essential for clinical translation. Overall, herbal hydrogel systems represent a promising strategy to advance DED management and improve long-term patient outcomes.