Rhophylac Dosage/Direction for Use

The following dose schedules are recommended based on the clinical studies performed with Rhophylac, however consideration must be given to professional guidelines for the use of anti-D IgG in the individual country of application.
The dose of anti-D immunoglobulin should be determined according to the level of exposure to Rh(D) positive red blood cells (RBCs) and based on the knowledge that 0.5 ml of packed Rh(D) positive RBCs or 1 ml of Rh(D) positive blood is neutralised by approximately 10 micrograms (50 IU) of anti-D immunoglobulin.
Dosage: Prevention of Rh(D) immunisation in Rh(D)-negative women: Antepartum prophylaxis: The recommended dose is a single dose of 300 micrograms (1,500 IU) administered by intravenous or intramuscular injection.
Planned antepartum prophylaxis: A single dose of 300 micrograms at 28 to 30 weeks of pregnancy. If the need for antepartum prophylaxis is identified in the period beyond 30 weeks of pregnancy, Rhophylac should not be withheld but administered as soon as possible.
Antenatal prophylaxis following complications of pregnancy: 300 micrograms should be administered by intravenous or intramuscular injection as soon as possible within72 hours after the at-risk event. If more than 72 hours have elapsed, the product should not be withheld but administered as soon as possible. If necessary, administration of anti-D IgG should be repeated every 6 to 12 weeks until the time of delivery.
Postpartum prophylaxis: 300 micrograms (1500 IU) should be administered as soon as possible within 72 hours of delivery of an Rh(D) positive (D, D^weak, D^partial) infant, by the intravenous or intramuscular route. If the 72-hour limit is exceeded, Rhophylac should be administered anyway. The postpartum dose must be given even when antepartum prophylaxis has been administered and even if residual activity from antepartum prophylaxis can be demonstrated in maternal serum.
If a large foeto-maternal haemorrhage (haemorrhage volume greater than 4 ml of Rh(D) positive foetal blood is suspected, e.g., in the event of foetal anaemia or intrauterine foetal death, its extent should be determined by a suitable method, e.g. Kleihauer-Betke test, and additional doses of anti-D should be administered as indicated (10 micrograms (50 IU) for each 0.5 ml of Rh(D) positive foetal RBCs or per 1ml Rh(D) positive foetal blood).
Incompatible transfusions of Rh(D) positive RBCs in Rh(D) negative patients: The recommended dose is 10 micrograms (50 IU) anti-D immunoglobulin per 0.5 ml of Rh(D) positive erythrocyte concentrate or 1 ml of transfused Rh(D) positive blood. The appropriate dose should be determined in consultation with a specialist in blood transfusion. Follow-up tests for Rh(D) positive RBCs should be done every 48 hours and further anti-D administered until all Rh(D) positive RBCs have cleared from the circulation. The intravenous route of administration is recommended as it will achieve adequate plasma levels immediately. If given by intramuscular administration the large doses should be administered over a period of several days. A maximum dose of 3,000 micrograms (15000 IU) is sufficient in the case of larger incompatible transfusions independent of whether the transfusion volume is greater than 300 ml of Rh(D)-positive blood or 150 ml of Rh(D) positive erythrocyte concentrate was transfused. Due to possible risk of haemolysis, however, it is suggested to not exceed the dose of 3000 micrograms (15000 IU).
The dose recommendations for prevention of Rh(D) isoimmunisation are summarized in the following table: (See Table 1.)

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Paediatric population: As the posology in case of incompatible transfusion depends on the volume of Rh(D) positive blood or Rh(D) positive RBC concentrate transfused, the recommended dose in children and adolescents (0-18 years) is not considered to be different to that of adults. However, the appropriate dose should be determined in consultation with a specialist in blood transfusion.
Elderly population: As the posology in case of incompatible transfusion depends on the volume of Rh(D) positive blood or Rh(D) positive RBC concentrate transfused, the recommended dose in elderly patients (≥65 years of age) is not considered to be different to that of adults. The appropriate dose, however, should be determined in consultation with a specialist in blood transfusion.
Method of administration: For intravenous or intramuscular use.
As with all blood products, patients should be observed for at least 20 minutes following administration of Rhophylac.
Rhophylac can be administered by intravenous or intramuscular injection.
In case of haemorrhagic disorders where intramuscular injections are contraindicated, Rhophylac should be administered intravenously. If large doses (>5 ml) are required and intramuscular injection is chosen, it is advisable to administer them in divided doses at different sites.
Obesity: In patients with a body mass index (BMI) ≥30 intravenous administration should be considered (see Precautions).