SAFETY AND TOLERABILITY OF PROBIOTIC AND SYNBIOTIC SUPPLEMENTATION DURING CHEMOTHERAPY

Chemotherapy, while essential in cancer treatment, often causes gastrointestinal (GI) toxicity due to its damaging effects on the gut epithelium and disruption of the microbiota. Probiotic and synbiotic supplementation has emerged as a promising adjunct to alleviate these side effects by modulating gut microbiota, enhancing mucosal integrity, and reducing inflammation. This review synthesizes current evidence on the safety and tolerability of probiotics and synbiotics during chemotherapy. Clinical trials have demonstrated reductions in chemotherapy-induced diarrhea, mucositis, and abdominal discomfort, particularly with strains like Lactobacillus and Bifidobacterium. Synbiotics offer additional benefits by enhancing probiotic survival and activity through prebiotic synergy. However, safety concerns remain, especially in immunocompromised patients, with rare reports of probiotic-associated infections. Most adverse effects are mild and transient, such as bloating or flatulence. Guidelines recommend cautious use, emphasizing strain specificity, product quality, and individualized risk assessment. Despite encouraging outcomes, challenges such as study heterogeneity, lack of standardized protocols, and product variability persist. Future directions include large-scale trials, personalized supplementation based on microbiome profiling, mechanistic studies, and development of regulatory standards. With appropriate clinical oversight, probiotics and synbiotics hold potential as safe, effective, and patient-friendly interventions to support cancer therapy.