A 73-year old patient suffering from IgM-paraproteinemia, plasma hyperviscosity, and acquired v. Willebrand's disease developed two consecutive bleeding episodes. He was treated by double-bag plasmapheresis and double-bag plasmapheresis combined with DDAVP. This combined therapy was superior to plasmapheresis alone, since bleeding ultimately stopped and did not reoccur. Thus, labour and expense of large volume plasma exchange and the costs of F VIII therapy could be prevented.