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.