Last July, I wrote about Probiotics, and my success with them in controlling persistent. unexplained gastro-intestinal distress.  A few friends wrote in with other suggestions, and then I discovered Nature's Way Primadophilus Optima. It has a wide spectrum of bacterial strains (14) and a very high potency: 35 million CFU/capsule, guaranteed through the shelf-life of the product.  In addition, it has an enteric coating to ensure that the probiotics are delivered to the gut and not destroyed by stomach acid, and a reasonable price — around $30 for a 2-month supply (60 capsules).  Buy it for $31.32 with free shipping from Amazon.com, or as low as $28.75 when you buy at least 3 bottles from VitaDigest.com. (Save an additional $3 with coupon: CS3SAVINGS.