Regarding Diquafosol ophthalmic solution comprising a chelating agent, formation of insoluble precipitates found in Diquafosol ophthalmic solution during its storage, as well as deterioration of the filtration performance in the course of production (filtration sterilization), have been inhibited. Further, in Diquafosol ophthalmic solution comprising a chelating agent, enhancement of preservative effectiveness has been confirmed. Accordingly, the present invention provides Diquafosol ophthalmic solution having physicochemical properties that are stable during the courses of production and distribution as well as the course of storage by a patient. Particularly in the course of production, the solution can be subjected to efficient filtration sterilization. Moreover, the solution has excellent preservative effectiveness. The present invention also provides a method for inhibiting formation of insoluble precipitates from an aqueous ophthalmic solution comprising diquafosol or a salt thereof, by adding a chelating agent to the solution.
