Recently, our knowledge of gut microbiota (GM) disorders in various pathologies has significantly increased. In particular, to date, there is sufficient evidence that various disorders of GM may play a pathogenetic role in irritable bowel syndrome (IBS). Therefore, various methods of GM modification are now considered as a new promising strategy for the treatment of patients with IBS. The use of probiotics, prebiotics, synbiotics, antibiotics and fecal microbiota transplantation (FMT) are considered as methods of GM modification. Many clinical trials have been conducted to examine the therapeutic effect of probiotics on general or specific symptoms of IBS, but most of these studies have been very heterogeneous. Although some meta‑analyzes or systematic reviews show that probiotics may be useful in treating the symptoms of IBS, their findings in the studies differ due to insufficient sample size, poor study design, and the use of different probiotic strains. Currently, only one selective intestinal antibiotic with eubiotic properties is known — rifaximin, the effectiveness and safety of which have been proven in large randomized trials. The authors presented their own experience of rifaximin use at IBS that confirmed its efficiency. Own experience of the FMT conduction in patients with IBS is also presented. It has been revealed that even one‑time treatment significantly affected the GM by reducing the frequency and severity of dysbiotic disorders; it was accompanied by significant clinical effects in most patients that lasted up to 3 months of follow‑up.