In the past few years, intestinal microbiota has emerged as a novel target for the treatment of
gut–brain axis alterations. These include functional gastrointestinal disorders, such as
irritable bowel syndrome (IBS), which can be comorbid with stress-related psychiatric
conditions. Thus, modulation of the microbiota (eg with the use of probiotics) could be
proposed as a novel strategy not only for the treatment of IBS but also as an adjuvant for
psychiatric treatment of anxiety and depression.