Intravenous immunoglobulin and intravenous anti-D are common therapies in the management of patients with immune thrombocytopenia (ITP). Both are pooled plasma products and both result in an increase in the platelet count in approximately 60% to 70% of patients with ITP. Despite immediate increases in the platelet count, the duration of response is limited, with platelet increments lasting between 2 and 4 weeks. Infusion reactions are common but adverse events rare. Although responses are similar, human and murine data suggest that the mechanisms of action of these treatments are complex and likely different.