The purpose of this study is to evaluate if ingestion of a probiotic formula (Jarrow-Dophilus EPS)reduces incidence of diarrhea and improves the quality of life of patients receiving antibiotic therapy.

A common complication of antibiotic use is antibiotic-induced diarrhea (AAD). AAD is the result of disrupted microflora, occurring two to eight weeks after antibiotic use. Probiotic supplementation may rebalance the intestinal flora, thus reducing the incidence of diarrhea, improving quality of life and reducing symptoms associated with antibiotic administration.

The proposed study will be a prospective, randomized, double blind, placebo-controlled trial that will assess the efficacy of the Jarro-Dophilus EPS probiotics formula for the prevention of AAD.

In addition,a subgroup of participants will be requested to provide one fecal sample at the initiation of the study and one sample in the last three days of probiotic (or placebo) treatment. The samples will undergo microbial analysis for routine C & S(Salmonella, Shigella, Campylobacter, Ecoli 0157, Yersinia), VRE, Yeast, Fungus culture (moulds) and C. difficile toxin.

Inclusion Criteria:

• 18-75 years of age
• Prescribed oral or IV antibiotics by physicians in Saskatoon Health Region's community medical clinics

Exclusion Criteria:

• Treatment with an antibiotic two weeks prior to study entry
• Underlying long term gastrointestinal disease (i.e., Ulcerative Colitis, Crohn's Disease, irritable bowel syndrome, ileostomy, colostomy)
• Pregnant or lactating
• Immunocompromised state
• Chronic illness such as Hepatitis B, Hepatitis C, renal failure
• Inability to provide informed consent, inability to speak or write in English
• Receiving tube feeds
• Insufficiently functional (physically and cognitively) to complete the study diary and questionnaires.