Anti Rh D Immunoglobulin is a sterile, concentrated solution of immunoglobulin G (IgG) containing antibodies against the Rh D antigen on red blood cells. It is prepared from pooled human plasma from donors with high titers of anti-D antibodies. In the Indian context, it is a critical biological used for the prevention of Rh D alloimmunization in Rh D-negative individuals exposed to Rh D-positive red blood cells, primarily during pregnancy and childbirth. It works by binding to and facilitating the clearance of fetal Rh D-positive red cells from the maternal circulation, thereby suppressing the maternal immune response and preventing the formation of anti-D antibodies that could harm future Rh D-positive pregnancies.
Adult: Standard prophylactic dose: 300 mcg (1500 IU) intramuscularly, given within 72 hours of a sensitizing event (delivery, abortion, procedure). For events before 12 weeks gestation, a mini-dose of 50-75 mcg (250-375 IU) may be used. Dose must be adjusted based on the volume of fetomaternal hemorrhage (FMH) as determined by tests like the Kleihauer-Betke test or flow cytometry. For larger FMH (>15 mL fetal RBCs), additional vials are required (300 mcg per 15 mL fetal RBCs or 30 mL whole blood).
Note: For intramuscular use: Administer by deep IM injection into the deltoid or gluteal muscle. Do not administer intravenously unless the product is specifically licensed for IV use. Inspect vial for particulate matter or discoloration before use. Use a separate sterile syringe and needle for each patient. For IV use (specific brands): Infuse at a rate as per manufacturer's instructions, usually starting slowly. Post-injection, apply pressure to the site to prevent bleeding and hematoma.
Anti-D Immunoglobulin contains high titers of IgG antibodies specific for the Rh D antigen. When administered to an Rh D-negative individual, these antibodies bind to any circulating Rh D-positive fetal red blood cells that have entered the maternal bloodstream. This antibody coating (opsonization) marks the fetal cells for rapid destruction by macrophages in the spleen, thereby clearing them from circulation before they can be recognized by the maternal immune system's B-cells. This prevents the initiation of a primary immune response and the subsequent production of maternal anti-D IgG antibodies.
Pregnancy: Pregnancy Category C (US FDA). It is specifically indicated for use in pregnancy to prevent Rh alloimmunization. Extensive clinical experience confirms its safety for the fetus when used as indicated. It does not cross the placenta in significant amounts to affect an Rh D-positive fetus when given prophylactically to the mother.
Driving: Unlikely to affect driving ability. Patients should be advised that dizziness or malaise can occur post-injection.
| Live Virus Vaccines (e.g., MMR, Varicella, Yellow Fever) | Anti-D Immunoglobulin may interfere with the immune response to live virus vaccines. Vaccination should be deferred for at least 3 months after administration. | Major |
| Other Immunoglobulin Preparations | May increase the risk of systemic adverse reactions. | Moderate |
| Anticoagulants (e.g., Warfarin, Heparin) | Increased risk of hematoma at the injection site for IM administration. | Moderate |
Same composition (Anti Rh D Immunoglobulin (NA)), different brands: