Composition and properties of IVIg preparations that affect tolerability and therapeutic efficacy

The use of intravenous immune globulin (IVIg) has increased significantly in the past decade, benefiting a wide variety of immune diseases. Seven different formulations of IVIg are now licensed in the United States. Although all contain pooled IgG, there are differences in their production and composition that affect their efficacy, tolerability, and side-effect profile. Important variables include concentration, volume, osmolality, sodium, and sugar content. This article reviews what is known about the composition and properties of the various IVIg formulations that might affect the therapeutic outcome.