Abstract
BACKGROUND: Fibromyalgia syndrome (FMS) and irritable bowel syndrome (IBS) frequently coexist, compounding disease burden and complicating treatment approaches. Despite the prevalence of this comorbidity, evidence on effective management strategies remains scarce. OBJECTIVE: This systematic review evaluates the efficacy and safety of oral pharmacological and dietary interventions for patients diagnosed with both FMS and IBS, following PRISMA guidelines. METHODS: A systematic literature search was performed on September 12, 2024, utilizing the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (PubMed), Web of Science, EMBASE, and Ovid to identifying randomized control trials evaluating interventions for FMS comorbid with IBS. The outcome encompassed pain reduction, global well-being, depressive symptoms, health-related quality of life, and safety profiles. RESULTS: The initial search yielded 784 studies, with 364 retrieved after applying inclusion criteria. Following duplicate removal and further screening, five randomized control trials met eligibility criteria. Of these, three were included in the meta-analysis. These trials investigated the effects of pharmacological agents, dietary modifications, and probiotics on pain and quality-of-life measures in patients with FMS-IBS comorbidity. Meta-analysis showed a statistically significant reduction in pain Visual Analog Scale (VAS) scores in groups receiving cyclobenzaprine and pregabalin, while probiotics demonstrated no significant benefit over placebo. Dietary interventions showed mixed results, providing symptom relief in selected patients. Adverse effects were highest in the cyclobenzaprine 30 mg group but were generally well tolerated in other interventions. CONCLUSION: Pharmacological treatments appear effective in reducing pain associated with FMS and IBS. Dietary interventions, such as monosodium glutamate (MSG) elimination, may benefit specific subgroups, while probiotics showed limited efficacy.