Plasmapheresis or therapeutic plasma exchange is a procedure designed to deplete the body of blood plasma without blood cells. Whole blood is removed from the body, the plasma is separated from the cells, and the cells are suspended in saline before being returned to the patient. The procedure is used to remove excess antibodies, immunoglobulins, or cytokines from the blood in various clinical situations. The particles removed should be adequately large (>15 kDa) and have a relatively long half-life. The volume of removed plasma should be based on body weight and haematocrit, and in an adult patient be in range of 2.5-2.7 litres (30-40 mL kg(-1)). To remove 90% of a harmful substance, four to five exchanges are necessary. In the review, several modes of plasmapheresis are described. The most common indications for plasmapheresis in patients treated in an ITU are: thrombotic thrombocytopenic purpura, Waldenström macroglobulinemia, Guillain-Barre syndrome, chronic inflammatory poliradiculopathy, myasthenia gravis, or Lambert-Eaton syndrome.The procedure is safe, and complications are rare and not serious.