Absolutely, you can refrigerate Nordic Flora Probiotics, but you do not have to. Refrigeration will help extend the life of the probiotic bacteria, however, they are guaranteed through the end of their shelf life even without refrigeration, as long as they are stored in a cool, dry place.
The probiotic strains used in Nordic Flora are a blend of hardy strains, which are encapsulated while in a dormant state. Once consumed, the strains are exposed to heat and moisture in the digestive tract, at which point they become active again.