Immunoglobulin therapy for immunodeficiency.

Immunoglobulin replacement is donor-derived pooled immunoglobulin G, which provides passive immunity to patients with antibody deficiency or dysfunction. It may be administered either intravenous or subcutaneous routes. Intravenous immunoglobulin is administered at higher doses every 3-4 weeks, whereas most forms of subcutaneous immunoglobulin are administered at lower doses, usually every 1-2 weeks. Benefits and risks, including adverse effects, convenience, and cost vary according to route of administration. Immunoglobulin products also differ in their composition, so patient-specific comorbidities are important to consider when selecting an immunoglobulin product. We discuss adverse effects associated with immunoglobulin therapy, their associated risk factors, treatment, and ways to mitigate these risks. Finally, the laboratory monitoring and vaccination recommendations for patients on immunoglobulin replacement therapy are reviewed.