Pharmacology · Immunoglobulins and antitoxins
Normal human immunoglobulin (IVIG) !
IgG pooled from the plasma of thousands of donors. It replaces antibodies in immunodeficiency and modulates the immune system in autoimmune disease.
Updated 2026-11-01
Also called: Intravenous immunoglobulin (IVIG), Gamma globulin, Subcutaneous immunoglobulin
Mechanism of action
It contains the IgG antibodies present in most of the population. In humoral immunodeficiency it supplies the antibodies the patient does not make. At high doses it modulates immunity in several ways: it blocks Fc receptors, speeds catabolism of antibodies (autoantibodies included), increases regulatory T cells and binds pathological antibodies. The exact mechanism is not fully known.
- Supplies polyclonal IgG from many donors
- Replaces missing antibodies in immunodeficiency
- At high doses blocks Fc receptors and speeds autoantibody clearance
- Less platelet destruction and immune inflammation
Pharmacokinetics
- Distribution
- Intravenous; distributes in plasma and extracellular fluid
- Half-life
- About 23 days for human IgG
Indications
- Primary humoral immunodeficiency
- Immune thrombocytopenic purpura
- Immune neuropathies (chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy)
- Kawasaki disease, to prevent coronary aneurysms
Adverse effects
Common
- Headache, fatigue, nausea
- Chills, fever and flushing during the infusion
- Transient hypotension and itching
Contraindications
- IgA deficiency with anti-IgA antibodies
- Previous anaphylaxis to immunoglobulins
Key interactions
- Live virus vaccines (measles, mumps, rubella, varicella)
- Transferred antibodies reduce the vaccine response; they are spaced apart in time
What is monitored
- Kidney function and hydration status
- Signs of thrombosis in at-risk patients
- Vital signs during the infusion
- Haemoglobin if haemolysis is suspected
Administration and safety
- Intravenous infusion in a health facility, given by health staff
- Follow the product's instructions on preparation and compatibility
- It is a blood product: record product and batch
Nursing care
- Ensure good hydration before the infusion
- Take vital signs at the start and during the infusion
- Watch for severe headache with neck stiffness, dark urine or breathlessness
- Ask about IgA deficiency and previous reactions
Pregnancy and breastfeeding
Used in pregnancy when indicated; IgG crosses the placenta, mostly late in gestation.
Test yourself
Think of the answer, then tap the question to see it.
Which patients are at risk of anaphylaxis with intravenous immunoglobulin?
Those with IgA deficiency and anti-IgA antibodies, because the product contains traces of IgA.
What are the two serious boxed warnings of intravenous immunoglobulin?
Thrombosis and kidney injury, especially in older adults, with dehydration or pre-existing kidney disease.
What is intravenous immunoglobulin used for in Kawasaki disease?
To prevent coronary artery aneurysms.
Related drugs
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Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: Immune Globulin Intravenous (Human)(IVIG): MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2025); Farmacología básica y clínica (Katzung), appendix (vaccines and immune globulins) (McGraw Hill, 2025); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026); eEML - Electronic Essential Medicines List (World Health Organization, 2025).
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Representative model, for educational purposes only.