Hello! The shelf life of koryo ginseng tea and plant foods in general is two years. Generally speaking, herbs do not exceed two years, woody plants do not exceed four years, and minerals do not exceed 10 years. Some herbs have been stored for a long time, and although there is no mold or insect damage in appearance, the existing efficacy is reduced. If the package has been opened and stored in the refrigerator for refrigeration, it can only be preserved to half a year - three months. Chinese medicine and such custody, in the case of our naked eye can not see, it is easy to ignore the quality, if the expiration date, easy to be oxidized, mold, pollution, etc., the medicinal properties of the reduction, consumption is easy to have adverse reactions occur. Suggest you treat it with caution. Goodbye!