Anti Rh D Immunoglobulin (50mcg) is a sterile, concentrated solution of immunoglobulin G (IgG) containing antibodies against the Rh D antigen. It is derived from human plasma collected from screened donors. In the Indian context, it is a critical biological agent used for the prevention of Rh D alloimmunization (Rh sensitization) in Rh D-negative individuals exposed to Rh D-positive red blood cells. The 50mcg dose is typically used for specific indications like post-miscarriage or post-abortion prophylaxis.
Adult: Standard postnatal dose: 300mcg (1500 IU) within 72 hours of delivery. The 50mcg (250 IU) dose is specifically indicated for events before 20 weeks gestation (e.g., miscarriage/abortion up to 12 weeks) or for very small fetomaternal hemorrhages (<2.5ml of fetal RBCs) as determined by a Kleihauer test.
Note: For 50mcg dose: Administer by deep intramuscular injection, preferably into the deltoid muscle or anterolateral aspect of the thigh. Do not administer intravenously unless the product is specifically licensed for IV use. The injection should be given within 72 hours of the sensitizing event for optimal efficacy, though administration up to 9-10 days post-event may still offer some benefit.
Anti Rh D Immunoglobulin contains high titers of antibodies specific to the Rh D antigen present on the surface of red blood cells (RBCs). When administered to an Rh D-negative individual, these antibodies bind to any circulating Rh D-positive fetal RBCs that have entered the maternal circulation. This opsonization marks the fetal cells for rapid destruction by macrophages in the spleen, thereby clearing them from the bloodstream before the mother's immune system can recognize the Rh D antigen and mount a primary, active immune response.
Pregnancy: US FDA Category C. It is specifically indicated for use in pregnancy to prevent HDFN. Extensive clinical experience confirms its safety when used for the recommended indications. It does not cross the placenta in significant amounts to affect the current fetus when given to the mother.
Driving: Unlikely to affect driving ability. Patients should be advised regarding potential dizziness or malaise.
| Live Attenuated Vaccines (MMR, Varicella, Yellow Fever) | Anti-D Ig may interfere with the immune response to the live vaccine, potentially reducing its efficacy. | Major |
| Other Immunoglobulins | May increase the risk of systemic adverse reactions. | Moderate |
Same composition (Anti Rh D Immunoglobulin (50mcg)), different brands: