Benjamin Prince, MD, MSCI, FAAAAI, allergist/immunologist at Nationwide Children’s Hospital in Columbus, Ohio, discusses when to consider starting IgG replacement therapy. IgG replacement therapy is pooled antibody from healthy individuals that has been purified and is given to patients with antibody deficiency. Patients with antibody deficiency experience frequent and recurrent infections, including pneumonia, etc. Blood testing can be done to look at the antibody classes you produce and the quality of those antibodies, as well as the B cell population characteristics. Dr. Prince indicates that IgG can be administered intravenously at the hospital or subcutaneously, which is more convenient and can be done at home. IgG replacement therapy has revolutionized the treatment of these patients, and is well tolerated and can help protect patients against dangerous infections.