Abstract

SITU GELLING SYSTEM: NOVEL APPROACH FOR OPHTHALMIC DRUG DELIVERY

Rajeshwari N. Patil*, Rachana S.Kumar

ABSTRACT

Eye is the most vital organ of body. In ocular drug delivery the physiological constraints imposed by the protective mechanisms of the eye lead to low absorption of drugs, resulting in a shorter duration of the therapeutic effect. Conventional dosage forms (such as Eye drop, ointments, gels etc.) suffer from disadvantages like low residence time, blurred vision, frequent dosing. To overcome the limitations associated with conventional system, newer drug delivery system were developed. Newer research in ophthalmic drug delivery systems is directed towards a amalgamation of several drug delivery systems, that include to build up systems which not only prolong the contact time of the vehicle at the ocular surface, but also slow down the removal of the drug. In situ gels are in liquid phase while instillation but changed to gel in response to stimuli (which may be temperature, pH, ion, UV radiation). These stimuli also serve as basis for type of In situ gelling system. These systems not only help to increase in precorneal residence time of drug to a sufficient extent, so that drug can exhibit its maximum biological action but also decreases the systemic side effects to create a more pronounced effect with lower doses of the drug. Continuous delivery of drugs in a controlled manner to the anterior chamber of the eye will also eliminate the requirement for frequent drug administration, causing better patient compliance and thus serves as best alternative to conventional ophthalmic drops. In this article, an attempt has been made to highlight the important technical and pharmaceutically relevant concepts related with drug delivery systems developed for administration through the Ocular route.

Keywords: Ophthalmic Delivery System, In-Situ Gel, Hydrogel, Phase Transition Systems.