For a study, irritable bowel syndrome (IBS) was a chronic functional illness whose onset may be connected to intestinal dysbiosis, both directly and indirectly. The researchers looked into the relationship between IBS symptoms and the gut microbiome and the role of rifaximin (1200mg daily; 11.2g per treatment). The researchers gathered 72 patients, including 31 patients with IBS-D (diarrhea), 11 patients with IBS-C (constipation), and 30 patients with IBS-M (mixed constipation and diarrhea), as well as 30 healthy controls (HCs). Patients with IBS-D, IBS-C, and IBS-M, respectively, saw 68%, 64%, and 53% improvement after using rifaximin for 10–12 weeks. Stool samples were taken before and after treatment, and fecal microbiota profiles were determined using deep sequencing of 16S rRNA. In contrast, hydrogen 1-nuclear magnetic resonance (1H-NMR) and gas chromatography-mass spectrometry (GC-MS) determined stool metabolic profiles. Only Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria were consistently found in all samples out of the 26 recognized species. In fecal samples from HCs and IBS-D and IBS-M participants, Bacteroidetes predominated, whereas Firmicutes predominated in those from IBS-C subjects. All IBS patients were distinguished from HCs by species richness but not community diversity. HCs were differentiated from all IBS patients utilizing metabolic fingerprinting using NMR spectra. About 13 metabolites were different between HCs and IBS patients using GC-MS. Neither metagenomics nor metabolomics analysis, on the other hand, revealed any significant differences between patients who improved following treatment and those who did not.