Rho(D) immune globulin (RhoGAM, Gamulin Rh, HypRho D, MicRhoGAM, Rhesonativ, HyperRHO, Rhophylac, WinRho SDF)
Classes: Immune Globulins
Dosing and uses of RhoGAM, Gamulin Rh (Rho(D) immune globulin)
Adult dosage forms and strengths
WinRho SDF, Rhophylac given IV/IM; others IM only
1500 International Unit ~300 mcg
Administer to Mother to Prevent Hemolytic Disease in Newborn
Antepartum: 1500 IU/300 mcg IV/IM at 28-30 weeks of gestation
Postpartum: 1500 IU IV/IM within 72 hr
If both given risk reduced to 0.1%
If unable to give within 72 hr, give within 28 d; do not withhold
If >15 mL of Rho+ fetal RBC present in mother's circulation, multiple 1500 IU doses are required
Obstetric Conditions (Abortion/Miscarriage)
1500 IU IV/IM x1 within 72 hr
HyperRHO/MicRhoGAM: If abortion within 13 weeks give 250 IU/50 mcg (minidose)
Immune Thrombocytopenic Purpura (Nonsplenectomized Rho(D)-Positive Patients)
Initial, Hgb >10 g/dL: 250 IU/kg IV x1
Initial, Hgb <10 g/dL: 125-200 IU/kg IV x1
Additional doses: 125-300 IU/kg IV PRn
Infuse IV over 3-5 min
If unresponsive to intital dose and Hgb <8 g/dL, use an alternate treatment
Incompatible Transfusions
WinRho SDF
- Exposure to Rh(D) positive whole blood
- IM: 12 mcg (60 IU)/mL blood
- IV: 9 mcg (45 IU)/mL blood
Rhophylac
- 20 mcg (100 IU)/2 mL blood (or 1 mL erythrocyte concentrate) IV/IM
Other Indications & Uses
To suppress immune response of Rho negative mothers exposed to Rho positive blood due to Rho positive neonate during childbirth, and thereby prevent hemolytic disease of newborn in future pregnancies
To suppress Rho immune response in Rho-negative women during obstetric complications or invasive procedures
Immune Thrombocytopenic Purpura in nonsplenectomized Rho(D)+ patients
Incompatible transfusions (Rho+ blood in Rho-negative individuals)
Pediatric dosage forms and strengths
Safety & efficacy not established; but given at doses proportionate with adult dose in childhood ITp
RhoGAM, Gamulin Rh (Rho(D) immune globulin) adverse (side) effects
Frequency not defined
Tenderness
Allergic reaction
Urticaria
Angioedema
Rare elevation in total bilirubin secondary to rapid RBC destruction when given following transfusion mismatch
Warnings
Black box warnings
Intravascular Hemolysis (IVH) with WinRho SDF
- Intravascular hemolysis (IVH) leading to death has been reported in patients treated for ITP with WinRho SDF
- IVH can lead to clinically compromising anemia and multisystem organ failure including acute respiratory distress syndrome (ARDS)
- Serious complications, including severe anemia, acute renal insufficiency, renal failure and disseminated intravascular coagulation (DIC) have also been reported
- Monitor closely in health care setting for at least 8 hr after administration
- Perform dipstick urinalysis at baseline, 2 hr, and 4 hr after administration and prior to end of the monitoring period
- Alert patients to signs and symptoms of IVH, including back pain, shaking chills, fever, and discolored urine or hematuria
- Absence signs and/or symptoms of IVH within 8 hr do not indicate IVH cannot occur subsequently
- Post-treatment laboratory tests should be performed if IVH suspected and include plasma hemoglobin, urinalysis, haptoglobin, LDH, and plasma bilirubin (direct and indirect)
Contraindications
Hemolytic Dz
- Rho(D)+
- Rho(D) negative women who are Rh immunized
- Hypersensitivity to immune globulins
Immune Thrombocytopenic Purpura
- Rho(D) negative individuals
- Splenectomized individuals
- Hypersensitivity to plasma products
- Autoimmune hemolytic anemia
- Pre-existing hemolysis or high risk for hemolysis
- Do not use WinRho SDF in patients with IgA deficency with antibioies against IgA
Cautions
NEVER GIVE TO NEONATe
Do not administer IM for ITp
WinRho SDF: risk of rare but potentially fatal intravascular hemolysis in ITP pts
Maltose-containing IVIG products (eg WinRho SDF) may give false highs in certain glucose-testing systems
Avoid live vaccines for 3 mth
IgA deficiency
Avoid gluteal IM if possible, if not inject only in upper outer quadrant
Pregnancy and lactation
Pregnancy category: C
Lactation: not known if excreted in breast milk, no adverse effects reported
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of RhoGAM, Gamulin Rh (Rho(D) immune globulin)
Half-Life: brand-dependent
Peak Plasma:
Im
- Time: 5-10 d
- Concentration: 18-19 ng/mL
IV
- Time: 2 hr
- Concentration: 36-48 ng/mL
Mechanism of action
Anti-Rho(D) immune globulins from human donors
Administration
IM
Administer to mother, not to infant
Administer into the deltoid muscle or upper outer side of the thigh
Do not use gluteal region as routine inj site (risk of injury to sciatic nerves), however if necessary, use only the upper, outer quadrant of gluteal muscle
The plunger of the syringe should be drawn back before injection to ensure that the needle is not in a blood vesseL
If blood or any unusual discoloration is present in the syringe, withdraw needle &discard syringe; administer new dose of Rho(D) IGIM at a different site using a new syringe & needle
Do not adminster RhoD IGIM by IV; however, RhoD IGIV may be administered Im
Do NOT administer IM for ITP Tx
WinRho SDF: dilute 600 IU & 1500 IU in 1.25 mL supplied diluent(s); for 5000 IU vial, use 8.5 mL
IV
For Rh suppression, administer to mother & not infant
Reconstitute vial contents with appropriate volume of NS by injecting supplied diluent (NS) slowly onto the inside wall of the vial & swirl vial gently until the lyophilized pellet has dissolved
Do not shake vial. Inspect for particulate matter and discoloration prior to administration
For 600 IU or 1500 IU vials, use 2.5 mL diluent; for 5000 IU vial, use 8.5 mL
Do not administer with other drugs
Administer direct inj Rhophylac at 2 mL/15-60 sec; WinRho SDF 1500 IU/5-15 sec