This formula has a 12 strain blend with a minimum of 12 billion live cells at expiry date (18 billion live cells per capsule at time of manufacture). These 12 strains include 8 lactobacilli species and one lactococcus species for the ultimate health of the full length of the small intestine as well as 3 bifidobacteria species for the ultimate health of the complete length of the large intestine. Different species in a single formula more closely approximates the normal composition of intestinal flora. As probiotic properties are different from one strain to the other, each strain will contribute specific inhibitive functions against pathogenic or putrefactive bacteria. Each strain has been selected for ability to grow in the presence of high bile levels. High growth in the presence of bile also maximizes probiotic potency. Antibiotic compatibility is also important. Strains are chosen so they do not interfere with the effectiveness of antibiotics but still protect from their adverse effects.