Sodium vitrate eye drops can be used for 4 weeks after opening, that is, not more than one month. Sodium vitrate eye drops are a commonly used eye drop that can be used for dry eyes, as well as dry corneas caused by contact lens wear or trauma from medications. Sodium vitrate eye drops after opening, after each use should be closed the lid, and placed in a cool dry place, the environment temperature is too high may lead to changes in the properties of the liquid efficacy. Eye drops can be used for up to 4 weeks after opening, but it is not recommended to use them for a longer period of time, as they may cause changes in their properties, affecting their effectiveness and even causing adverse reactions. The eye drops themselves are sterile, as opening them for a long time may cause bacterial contamination, which may lead to eye infections after use. Even within 4 weeks of opening, if the storage is not appropriate or found that there is a change in the properties of the liquid or itching and congestion after eye drops and other discomfort, you should stop the drug in time and go to the hospital. In addition, sodium vitrate eye drops should be used strictly according to medical advice.