Our manufacturers formulate their probiotics to ensure their products retain viability until they reach the consumer. But we take extra care, ensuring that all probiotics remain refrigerated in the OC Whole Family Wellness office until the time of shipment; they are then packaged in an insulated envelope with an ice pack to further ensure potency in transit—at no extra charge. (Note: Ice pack will not arrive frozen/product will not arrive cold).Additionally, probiotic manufacturers add extra colony forming units (CFUs) to adjust for the product being shipped unrefrigerated, even in the summer months, and for it being unrefrigerated for several weeks. To ensure potency, the CFU count on the package is lower per dose than the actual count at the time of production. The CFU count is valid through the expiration date, even after the package is opened. For long-term storage, the product should be refrigerated.About different probiotic types:Shelf-stable probiotics are room-temperature stable and do not require refrigeration. Refrigeration will, however, extend the shelf life. Avoid temperatures above 77°F (25°C).Saccharomyces Boulardii does not require refrigeration and can be stored at room temperature. Refrigeration will, however, extend the shelf life. Avoid temperatures above 77°F (25°C).Non-shelf stable probiotics are room-temperature stable, but should be refrigerated for full therapeutic effect and extended shelf life. Avoid temperatures above 77°F (25°C).