the understanding of the disease mechanism of guillain–barré syndrome has evolved in recent years. development of new treatments has been limited since immunotherapy was introduced in the 1980s and 1990s. current research is aimed at demonstrating whether some people who have received ivig might benefit from a second course if the antibody levels measured in blood after treatment have shown only a small increase. studies of the immunosuppressive drugs mycophenolate mofetil, brain-derived neurotrophic factor and interferon beta (ifn-β) have not demonstrated benefit to support their widespread use.