Open Label Trial of Nissle 1917

Background: Nissle 1917 is an E. coli based probiotic that has been successfully used in Europe for close to 100 years to treat largely gastrointestinal disorders like inflammatory bowel disease, gastroenteritis, and irritable bowel syndrome. In addition to those disorders, we believe that Nissle 1917 is a promising alternative therapy for prevention of urinary tract infections in susceptible individuals. Purpose: The Phase 1 trial will use Nissle 1917 in healthy adult patient volunteers for the first time in the United States. The investigators will track the frequency and incidence of side effects and adverse events. Participants: 20 adult (\>21 years of age) healthy volunteers Protocol: * Participants will enroll in our trial after a review of medical history and physical. * Participants will then take 30 day course of Nissle 1917 capsules * Investigators will telephone participants 1-2 weeks after they have begun the trial to assess for any side effects or adverse events * Subjects will also be provided with a diary to record any side effects or adverse events * At the end of 30 days, participants will return to clinic for a follow up visit to discuss any side effects or adverse events experienced during the trial and to return any unused medication * Investigators will again telephone all participants 28-35 days following completion of the study drug again to pose a questionnaire aimed at revealing any side effects or adverse events.