Probiotics are organisms which belong to the fungi or bacteria groups and affect e.g., bacterial flora in the intestinum or inflammation site by reduction of the condition. They are applied in many cases, such as food allergies, diarrhea, autoimmunologic disorders, and irritable bowel syndrome (IBS) that affects 10% of the world population. Due to the lack of proper pharmacological treatment which would result in complete remission, probiotic preparations which lead to a reduction of the symptoms are one of the most often used drugs. Among them,
1. Introduction. 2. Irritable bowel syndrome. 3. History. 4. Morphology. 5. Mechanism of action. 5.1. Luminal action. 5.2. Trophic action. 5.3. Anti-inflammatory action. 6. Taxonomy. 7. Probiotics. 8. Summary