Intravenous Immunoglobulin/Subcutaneous Immunoglobulin
Intravenous Immunoglobulin (IVIG) is a therapy treatment for patients with antibody deficiencies. It is prepared from a pool of immunoglobulins (antibodies) from the plasma of thousands of healthy donors. Immunoglobulins are made by the immune system of healthy people for the purpose of fighting infections.
IVIG is given as an intravenous infusion (through the vein in the arm), which takes several hours to complete. Frequency of infusions vary according to the patient’s need. It may be given as a one-time infusion (such as for Kawasaki’s disease). For other diseases, it may be given from anywhere between one to five days on a monthly basis. Frequency and duration of infusions depend on the underlying disease and the clinical course. IVIG can take several weeks to fully take effect. The dosing of IVIG also varies dependent on the condition being treated, but usually is based on body weight. In these diseases, IVIG therapy generally involves the use of 2 g/kg administered over either 2 or 5 consecutive days.
Currently there are formulations of immunoglobulin that can be administered under the skin (subcutaneous, or SCIG) if the intravenous option is not viable.
The majority of people do well with IVIG, experiencing only minor side effects. IVIG may cause infusion reactions, which may present as fevers, chills, flushing, rash, muscle aches, and nausea. Headaches are also relatively common. These are generally not severe and improve with analgesics and antihistamines.
Rarely, IVIG may cause aseptic meningitis (inflammation of the lining of the brain without an infection). The use of medications like steroids, non-steroidal anti-inflammatories (NSAIDs), acetaminophen, and diphenhydramine and staying well hydrated can help to prevent these complications. Among patients who have certain forms of IgA deficiency, a severe allergic reaction to IVIG can occur.
