Challenges of Intraocular Drug Delivery

Over the last decades, significant advances have been made in improving drug delivery to the eye and in maintaining therapeutic drug concentrations within ophthalmic tissues. Most pharmacologic management of external diseases of the eye consists in using topical application to the surface of the eye as drops. Recent advances in topical drug delivery have been made that improve ocular drug contact time and drug bioavailability, including the development of ointments, gels, liposome formulations, and various sustained and controlled-release substrates, such as the Ocusert, collagen shields, and hydrogel lenses.