DRUGS

2. INTRODUCTION
• In India the incidence of the Rh incompatibility is about 5-10% from
the hospital statistics. Less than 1ml of Rh- positive blood was shown
to sensitize volunteers with Rh- negative blood. In 90% of cases
sensitization occurs during delivery.
• Rh0(D) immune globulin (RhIG) is a medication used to prevent Rh
isoimmunization in mother who are Rh negative and to treat
idiopathic thrombocytopenia purpura(ITP) in Rh positive. It is often
given both during and following delivery.

3. MECHANISM OF ACTION
 Successful prophylaxis of RhD immunization by anti –D immunoglobulin is associated with a rapid
elimination of Rh(D) positive red blood cells (RBC) from the circulation of Rh(D) negative individuals.
 This clearance is mainly due to interaction of the anti-D coated RBCs with Fc gamma receptors bearing
mononuclear cells.
• The mode of action of anti-D may be merely
• To clear the D-positive cells from the circulation to the spleen by interaction of the IgG- coated red cells with
macrophages bearing IgG Fc receptors resulting in phagocytosis or lysis of the red cells.

4. • To prevent Rh isoimmunization in a non-sensitized Rh negative mother in following cases
1. First trimester:- spontaneous/ induced abortion, ectopic gestation.
2. Second trimester:- amniocentesis, second trimester MTP, fetoscopy.
3. Third trimester:- external cephalic version, antepaturm hemorrhage.
4. Delivery:- normal, forceps, vacuum extraction, LSCS. Postnatal women for non- sensitized women>-16
years who are Rh negative.