Abstract: A peritoneal dialysis composition containing an osmotic agent comprising a glucose polymer mixture, said mixture including at least 15% by weight of glucose polymers having a D.P. (degree of polymerization) greater than 12. A method is provided for preparing the glucose polymers and a defined sterile aqueous solution of the same for use in peritoneal dialysis by introduction into the abdominal cavity. Also disclosed are methods of treating toxaemia caused by toxins arising from internal disorders of the body, such as hepatic encephalopathy, or which arise from external sources such as poisoning by overdoses of drugs or industrial and agricultural chemicals, e.g., paraquat.