Review on the Challenges, Approaches & Applications of Ophthalmic Drug Delivery System

An ophthalmic drug delivery system is a method used to treat various ocular diseases and vision related conditions. It is used to treat macular degeneration, viral infections, glaucoma, ocular inflammations, dry eye syndrome and retinal degenerations. In this drug delivery system face to both the pharmaceutical and medical sciences significant obstacles. The primary challenge is maintaining an effective medicine concentration at the therapeutic target for extended periods. The corneas anatomy, physiology and barrier function work together to prevent rapid drug absorption. The various barrier properties overcoming the eye defenses without causing permanent tissue damage. Topical, systemic, periocular and intravitreal barriers are the main ophthalmic administration route. Some approaches are adding binding agents by molecular imprinting and entrapment of vesicular systems into the lens matrix. Various elimination mechanisms make it difficult for conventional ophthalmic drug delivery to the retinal tissues. Current ophthalmic drug delivery systems with lower bioavailability and invasive nature, pose challenges for novel technologies to improve treatment for ocular disorders. Hydrogels, polymer micelles, nanoparticles (NPs), implants, microneedles, ion electrophoresis, ultrasound and more new ophthalmic drug delivery methods have recently been developed. These systems are claimed to offer extended ocular surface residence time, thereby reducing the impact of natural eye clearance systems. Modern methods increase the therapeutic effectiveness of the ophthalmic route. Advances in nanotechnology and biomaterials science may development of smart technologies for enhancing ophthalmic drug delivery. This system would likely be more pseudoplastic than the materials currently in use and more hydrophilic to reduce blink noise.