Chronic constipation is prevalent in patients undergoing peritoneal dialysis (PD), raising the risk of catheter malfunction and transmural peritonitis. Gut dysbiosis in dialysis patients can worsen constipation. A single-arm prospective study was performed to assess the effectiveness of synbiotic (fructo-oligosaccharidesand Lactobacillus casei, Lacyobacillus rhamnosus, Lactobacillus reuteri, Saccaromycesboulardii) supplementation for 16 weeks in PD patients suffering from chronic constipation. The endpoints were the change in the constipation scoring system and in laxative use.