Study of Bio-K+® in the Reduction of the Risk of Clostridium Difficile Infection and Antibiotic Associated Diarrhea

Inclusion Criteria Only subjects who meet the following inclusion criteria will be eligible to participate in the study: * Are at least 18 years old * Able to tolerate food intake Antibiotic treatment started less than 48hrs from admission into the study * Have an expected hospitalization period of at least three days (including subject"s stay in the emergency room) * Speak and understand English and/or French. * Have an expected survival greater than 60 days * Agree to refrain from taking probiotic products (besides the study drug) during the study period Have given informed consent In addition, women of child bearing capacity who are not pregnant at the moment of screening (pregnancy test done on-site) and agree to use an acceptable form of birth control for the duration of the study (e.g. Condom, oral contraceptives, etc.) are allowed to participate. Exclusion Criteria Subjects who meet any of the following exclusion criteria will not be eligible to participate in the study: * Have been diagnosed with CDI in previous sixty days * Have taken Streptomycin, oral Vancomycin, or Metronidazole in the last 4 weeks, excluding as part of the treatment regimen triggering their inclusion into the study. * Are currently suffering from any health condition causing immunosuppression (including haematological malignancies, lymphoma, AIDS, transplant, and hemodialysis) * Have received more than 10 mg of prednisone per day for at least 1 month within 3 months prior to the participation to the study. * Have active diarrhea (three or more liquid stools per 24 hour period) or non-controlled intestinal disease/colitis such as Crohn's disease, ulcerative colitis or caeliac disease Have stomas, are ostomized or are parenteral nutrition users Have already been randomized to one arm of this study * Are known to have shown a previous reaction, including anaphylaxis, to any substance in the composition of the study products (i.e. Non-medicinal ingredients: Cellulose, hypromellose, medium chain triglycerides, sodium alginate, ascorbic acid, magnesium stearate (vegetal source), silicon dioxide and titanium dioxide * Where receiving systemic antibiotics on admission to the hospital or who have been treated with antibiotics over the past two weeks Have lactose intolerance or milk allergy * Have difficulties giving informed consent because of chronic mental disease, dementia * Are not likely to comply with study requirements (provide stool for screening if diarrhea or answer to the follow up questionnaires) * Have been known to use illicit drugs in the last two years. Have participated in another clinical study in the last 30 days * Female subjects that are pregnant, or who intend to become pregnant or are lactating during the study period * Female subjects of child bearing potential not currently using adequate contraception