Immune globulin ( γ-globulin, immunoglobulin
[Ig] G) is a fraction obtained from the plasma of normal indi-viduals and is
rich in antibodies found in whole blood.
It consists primarily of IgG
and contains trace amounts of IgA and IgM. -Globulin
provides the patient with passive
immunity and does not require time for the de-velopment of an antibody
response. It is believed to in-hibit viral penetration of host cells,
opsonize viral parti-cles, activate complement, and stimulate cell-mediated
γ-Globulin is administered
parenterally. Intramuscular or intravenous injections are given during the
early in-fectious stage to alleviate the progression of certain vi-ral
disorders. Protection lasts for 2 to 3 weeks after a single injection, although
for prolonged infections, in-jections can be repeated every 2 to 3 weeks.
Human immune globulin preparations
specifically for the treatment and/or prevention of CMV (CytoGam), HBV (BayHep B),
rabies (BayRab), RSV (RespiGam), and VZV (VZIG) are obtained from individuals with high titers of antibodies
against these viruses. A pooled het-erogeneous human immune globulin solution (BayGam, Gamimmune, others) can be used to lessen the likelihood of measles, varicella, or rubella
infection in individuals ex-posed to these viruses. Immune globulin also can be
used as an adjunctive form of therapy with other therapeutic approaches.
(e.g., anaphylaxis, angio-edema) associated with -globulin are rare but occur
most commonly in individuals with agammaglobuline-mia, severe hypogammaglobulinemia,
or IgA deficiency. The likelihood of anaphylactoid reaction increases
fol-lowing repeated dosing and for certain preparations, in-travenous
administration. Immune globulins can also cause urticaria, angioedema, fever,
and injection site re-actions. Preparations that are administered
intra-venously (e.g., RSV immune globulin) can produce in-fusion-related side
effects such as flushing, dizziness, blood pressure changes, palpitations,
abdominal cramps, and dyspnea; slowing the infusion rate may reduce the
severity of these effects. High doses of immune globu-lins have been associated
with rare cases of aseptic meningitis syndrome. A possibility of infection by
blood-borne pathogens exists with immune globulin and other human blood
products. Although prepara-tions are screened for contamination and viral
inactiva-tion processes are used, the risk of transmission of new or undetected
pathogens cannot be eliminated.
Treatment with immune
globulin can interfere with the response to live virus vaccines (e.g., measles,
mumps, rubella). Vaccinations should be deferred until several months after the
administration of -globulin because the antibodies contained in this
preparation may interfere with the development of the host immune response.
Individuals who were vaccinated shortly be-fore receiving immune globulin may
require revaccina-tion at a later time.