The Effect of Probiotics on Symptoms and Intestinal Flora in Patients With Irritable Bowel Syndrome

Inclusion Criteria: * Willing and able to provide informed consent * Age ≥18 and ≤70 years at Visit 1 * IBS according to the Rome III criteria * A score on abdominal pain NRS ≥3 and ≤6 at least two days a week measured the weeks before Visit 2 (baseline) * IBS-SSS ≥75 and ≤300 at Visit 2 (baseline) * Ability and willingness to understand and comply with the study procedures Exclusion Criteria: * Known intolerance or allergy to milk products (protein or lactose) or gluten * History of alcohol or substance abuse six months prior to screening * Known Hepatitis B or C or Human Immunodeficiency Virus (HIV) 1 or 2 * Female patients: currently pregnant or breast-feeding or intending to become pregnant during the study * Abnormal results of the screening laboratory tests clinically relevant for study participation, as judged by the Investigator * Other gastrointestinal disease(s) that explains the patient's symptoms, as judged by the Investigator * Other severe disease(s) such as malignancy, severe coronary disease, kidney disease or neurological disease, as judged by the Investigator * Symptoms indicating other severe disease(s) such as gastrointestinal bleeding, loss of weight or fever, as judged by the Investigator * Severe psychiatric disease as judged by the Investigator * Lack of suitability for participation in the study for any reason as judged by the Investigator * Use of other probiotic products from Visit 1 and throughout the study. * Consumption of antibiotic drugs 1 month prior to screening and throughout the study. * Consumption of drugs on a regular basis which could interfere with symptom evaluation as judged by the Investigator.