Summary: Gut microbiota plays a fundamental role in maintaining host homeostasis by influencing intestinal barrier integrity, immune function, metabolism, and gut‒brain axis communication. Increasing evidence indicates that disturbances in gut microbiota composition and function, known as dysbiosis, contribute to the pathogenesis of numerous gastrointestinal diseases, including irritable bowel syndrome (IBS), inflammatory bowel diseases (IBD), and symptomatic uncomplicated diverticular disease (SUDD). Antibiotic therapy remains one of the most important drivers of dysbiosis, often leading to long-term reductions in microbial diversity and metabolic imbalance. This review summarizes current knowledge regarding the role of dysbiosis in gastrointestinal disorders, with particular emphasis on sodium butyrate and targeted probiotic therapy. Mechanisms of action of selected probiotic strains, including Lactiplantibacillus plantarum 299v in IBS, multistrain formulations in IBD, and synbiotic approaches in diverticular disease are discussed. Particular attention is devoted to the synergistic interaction between sodium butyrate and probiotics, which may contribute to intestinal barrier restoration, inflammation reduction, and microbiota functional recovery. The article also presents pilot clinical data evaluating a combination of microencapsulated sodium butyrate and selected probiotic strains in patients with SUDD. The findings suggest significant clinical improvement, enhanced quality of life, and beneficial modulation of gut microbiota composition.