Primadophilus Bifidus Probiotic by Nature's Way is a probiotic blend boasting five million CFUs and four different strain blends made specifically for adults. These bacteria are taken to increase the body's immune system through the support and growth of beneficial microflora. Studies suggest they can ease symptoms associated with ulcers. Crohn's disease. colitis. irritable bowel syndrome and gut inflammation. To maintain potency. the product must remain refrigerated.