Rho(D) immune globulin

General

• Type: Immune Globulin
• Routes of Administration: IM, IV
• Common Trade Names: RhoGAM, WinRho

Adult Dosing

1st Trimester (<13weeks) Vaginal Bleeding

• 50 microgm IM
  • There is no harm in giving the standard 300 microgram dose, which is more readily available

2nd & 3rd Trimester Vaginal Bleeding

• 300 microgm IM once and send Kleihauer-Betke test
  • Within 72hrs give additional 300 microgm/15 ml Rh-positive blood

Pediatric Dosing

• Same as adult dosing above

Special Populations

• Pregnancy Rating: C
  • Animal studies have not been conducted, though available evidence suggest that administration of RhIG during pregnancy does not harm fetus
• Lactation risk:
  • Caution advised while breastfeeding, however no adverse events observed
• Renal Dosing
  • No dosage adjustments
• Hepatic Dosing
  • No dosage adjustments

Indications

• For risk of fetal maternal hemorrhage, such as blunt abdominal trauma
• Risk = >4-12wks
• Duration effect: 12wks
• Also given to Rh- male trauma patients who receive O+ blood to prevent future reaction with O+ transfusions

Contraindications

• Allergy to class/drug
• Prior sensitization of mother
• Known Rh-negative father
• Known Rh-negative fetus (from cord blood)

Adverse Reactions

Serious

• Anaphylaxis
• Viral transmission risk
• Acute intravascular hemolysis in patients with ITP
• Acute transfusion reaction

Common

• Fever
• Injection site reaction
• Headache
• Myalgias
• Fatigue

Pharmacology

• Half-life: Approximately 30 days
• Metabolism: Unknown
• Excretion: Unknown
• Mechanism of Action:
  • Exact mechanism unknown
  • Prevents isoimmunization by suppressing immune response by Rh negative individuals against Rh positive blood cells

See Also

• Vaginal Bleeding (Main)

External Links

• https://www.fda.gov/media/75013/download