Acidophilus is a bacteria that exists naturally in the body, primarily in the intestines and the vagina. Acidophilus helps maintain an acidic environment in the body, which can prevent the growth of harmful bacteria. Acidophilus has been used to treat or prevent vaginal yeast infections, yeast infections of the mouth, diarrhea caused by taking antibiotics, and urinary tract infections. It works by helping the body maintain normal consistency of bacteria in the stomach, intestines, and vagina. Check with your Health Care Provider before using this product.