Human Normal Immunoglobulin (16.5% w/v) is a sterile, highly purified, concentrated solution of immunoglobulin G (IgG) antibodies derived from pooled human plasma of thousands of donors. It contains a broad spectrum of IgG antibodies reflective of the donor population's immunity, providing passive immunity against a wide range of pathogens. The 16.5% concentration (165 mg/mL) is a high-strength formulation designed for subcutaneous administration (SCIg), offering a convenient option for home-based therapy, particularly for chronic conditions like Primary Immunodeficiency Diseases (PIDD).
Adult: **PIDD:** Initial dose typically 0.4-0.6 g/kg body weight IVIg monthly, converted to SCIg. **SCIg (16.5%):** Weekly dose is the previous monthly IV dose divided by the number of weeks (usually 4). Example: If monthly IV dose is 30g, weekly SCIg dose is ~7.5g. Infusion rate: Start at 10-20 mL/hr per site, can be increased gradually. **MMN/CIDP:** 0.4-0.6 g/kg IVIg monthly, with SCIg used for maintenance.
Note: For **SUBCUTANEOUS USE ONLY.** Administer using an infusion pump. Multiple infusion sites (typically 2-4, e.g., abdomen, thighs) can be used simultaneously to accommodate larger volumes. Pre-treatment with analgesics/antipyretics/antihistamines may be considered. Do not mix with other medications. Patient must be trained for self-administration at home.
Provides passive immunity by supplementing functional IgG antibodies. Mechanisms include: 1) **Neutralization** of pathogens (bacteria, viruses, toxins) by direct binding, preventing cellular attachment and invasion. 2) **Opsonization** of microbes, enhancing phagocytosis by neutrophils and macrophages via Fc receptor binding. 3) **Modulation of Immune Response** through Fc receptor blockade on dendritic cells and macrophages, suppression of inflammatory cytokines, and provision of anti-idiotypic antibodies that regulate autoreactive B-cells.
Pregnancy: Category C. Should be used during pregnancy only if clearly needed. IgG crosses the placenta, increasing from the 2nd trimester. Used in conditions like fetal alloimmune thrombocytopenia. Benefits must outweigh risks.
Driving: May cause dizziness, headache, or fatigue. Patients should be cautioned about driving or operating machinery until they know how the therapy affects them.
| Live Attenuated Vaccines (e.g., MMR, Varicella, Yellow Fever) | Immunoglobulin may interfere with the immune response to live vaccines. Vaccination should be deferred for at least 3 months (up to 12 months for measles) after last Ig dose. | Major |
| Other Immunosuppressants (e.g., high-dose corticosteroids, cyclophosphamide) | May have additive immunosuppressive effect, increasing infection risk. Conversely, may enhance immunomodulatory effects in autoimmune conditions. | Moderate |
| Loop Diuretics (e.g., Furosemide) | Concurrent use in patients with renal impairment may increase risk of renal dysfunction. | Moderate |
| ACE Inhibitors | May increase risk of anaphylactoid reactions in patients receiving Ig, especially those with IgA deficiency. | Moderate |
Same composition (Human Normal Immunoglobulin (16.5% w/v)), different brands: