Twenty patients with end-stage renal disease and a creatinine clearance of less than 5 ml/min were tre ated with oral gastrointestinal (GI) dialysis. The dialyzate contained an electrolyte solution with 180-220mmoles/l of mannitol. In fasting state in the morning the self-prepared 7 liters of dialyzate was drunk at a rate of one glass every 5 minutes for about 3 hours. Intermittent diarrhea with passage of watery fluid occurred during the whole period. After each treatment the average drop in BUN in individual patients was 11--22%, but no significant decrease in serum creatinine. With twice to thrice weekly GI dialysis uremic symptoms such as anorexia, nauseal and vomiting were usually improved with slight prolongation of life. However, treatment is usually difficult when the patient becomes oliguric or anuric, so its value in long-term management of chronic uremia is limited. Most of our patients either died or shifted to hemodialysis within a few months of institution of the therapy.