Background Neuromyelitis optica (NMO) is typically a severe relapsing inflammatory disease of optic nerves and spinal cord. Prednisolone, Azathioprine, Mycophenolate and Methotrexate are commonly used first-line immunosuppressants, stepping up to Rituximab if relapses occur.

Results We report 3 NMO/ NMO spectrum disorder patients who stabilised on maintenance IVIG.

Case 1: A 26 year-old woman who had 11 relapses over 10 years despite multiple immunosuppressants (including Rituximab) has remained in remission for 23 months with IVIG.

Case 2: A 47 year old woman with 6 relapses over 8 years despite immunosuppressants was started on Rituximab with good effect. But Rituximab had to be discontinued due to respiratory problems. After starting 6 weekly IVIG infusions she has had no further relapses after 2.8 years.

Case 3: A 59 year old woman with Aquaporin-4 antibody positive NMO spectrum disorder (3 episodes of severe optic neuritis over 5 years) was intolerant to Azathioprine (leukopenia). As baseline CD 19 counts were near 0, Rituximab was not given and she was initiated on 6 weekly IVIG and remains relapse free after 11 months.

Conclusions IVIG seems to be effective in preventing NMO relapses.