The capacity of charcoal to absorb endogenous and exogenous toxins is well established. It removes substances of higher molecular weight than standard dialysis membranes. The regular use of charcoal hemoperfusion as an adjunct to hemodialysis in chronic uremia is a real prospect capable of improving the patient's clinical and laboratory condition and/or reducing the weekly time of treatment. In line with our previous experience, 5 consenting informed patients on regular dialysis treatment from 9 to 35 months (residual creatinine clearance 0-1.8 ml/min, mean diuresis 350 ml) were treated without interruption for 5-8 months according to a schedule including two combined hemodialysis/hemoperfusion procedures instead of the previous three hemodialysis sessions. Patients were on adequate dialysis and their clinical, metabolic and laboratory conditions were stable. In the hemodialysis/hemoperfusion procedure a cartridge containing 150 g of methacrylate-coated activated charcoal with high biocompatibility was inserted in the dialysis circuit in series with a flat plate or hollow fiber dialyzer. Clinical, laboratory and metabolic conditions remained unchanged in all patients despite the one third reduction in dialysis hours per week. The tolerance of treatment was good: platelets, white cells and fibrinogen were unaffected. The marked reduction in weekly time of treatment led to a more satisfactory personal and social rehabilitation, enabling more patients to be treated with the same facilities.