It is a challenging task to administer the appropriate quantities of drugs to the eye mainly to the retina. Retinal transmission is urgently required due to potential vision loss caused by retinal disease. The failure to provide retinal transmission of topical or systemic routes is now widely accepted. The intravitreal path offers a high regional density of drugs which induces cataracts, retinal detachment, and endophthalmitis. Periocular route utilizing the sclera's permeability for the transmission of retinal dug. Systemically administered drugs must clear the retinal blood barrier (BRB) to show the action. The internal and outward flow of drugs is carefully regulated by highly specialized ocular barriers. A better understanding of these biological barriers could lead to new developments in ophthalmic drug therapy, including customised administration and minimally harmful side effects. This study primarily investigated the anatomical structure of the eye, specifically the blood-retinal barrier (BRB), different methods of drug administration, the importance of BRB physiology, such as its barrier functions, and the impact of influx and efflux transporters on delivering medications to the retina.