The procedure of Ig apheresis is not highly specific for pathogenic autoantibodies. During the procedure all immunoglobulins of class G and M are removed, including the immune complexes.

The peculiarity of autoimmune processes is that a wide range of antibodies are involved in them, and only a part of them is known. Furthermore, there are numerous autoimmune diseases of unkown etiology. Therefore, to effectively influence on the pathological process, the ability of eliminating all immunoglobulins and immune complexes is the most effective. Unlike the autoantibodies and immune complexes, the concentration of normal immunoglobulins quickly replenishes after the procedure.