Approximately 90% of all ophthalmic drug formulations are applied as eye-drops. While eye-drops are convenient and well accepted by patients, about 95-99% of the drug contained in the drops is lost due to absorption through the conjunctiva or through the tear drainage. A major fraction of the drug eventually enters the blood stream and may cause side effects.

Our group has focused on exploring the feasibility of using contact lenses for ophthalmic drug delivery. We have modeled the process of drug delivery by contact lenses to show that the fractional uptake by cornea can be increased to 50-70% by using contact lenses, which is at least an order of magnitude larger than that for drops. Typical contact lenses can only release drugs for a period of a few hours. Our group has also developed contact lenses that can release drugs for extended periods ranging from 5 days to months. The extended release is a result of creation of transport barriers in the lenses by either controlling the gel microstructure or by incorporating nano/micro particles that can release the drug for extended periods.