A punctal plug and method of treating dry eyes are provided. The punctal plug has two or three layer structure and contains at least one drug, for treating conditions such as dry eyes contained in a core, a potion of which is covered by a drug impermeable shell such that drug can radially diffuse from the core. The punctal plug can be inserted into a patient's upper punctum, lower punctum, or both to deliver the drug for an extended period of time. The drug for treating dry eyes can be, for example, cyclosporine A. The plug can also be used for extended delivery of ophthalmic drugs.
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