A live specific strain of the species, Lactobacillus rhamnosus (a subspecies of Lactobacillus casei) with probiotic activity. When administered orally, Lactobacillus rhamnosus GG adheres to the mucous membrane of the intestine and may help to restore the balance of the GI microflora; promote gut-barrier functions; diminish the production of carcinogenic compounds by other intestinal bacteria; and activate the innate immune response and enhance adaptive immunity, especially during infections. Check for active clinical trialsusing this agent. or A live form of a bacterium that makes lactic acid (a substance that is made from sugars found in milk and is also made in the body). Lactobacillus rhamnosus GG is given to help with digestion and normal bowel function. It may also help keep the gastrointestinal (GI) tract healthy. It is being studied in the prevention of infections in patients having donor stem cell transplants and in other conditions. Also called Culturelle.