Rho(D) immune globulin

(Redirected from RhoGAM)

General

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

Adult Dosing

1st Trimester (<13weeks) Vaginal Bleeding

  • 50 microgm IM[1]
    • 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[2]
  • 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[3]

Contraindications

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

Adverse Reactions

Serious

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

Comments

See Also

External Links

References

  1. RhD alloimmunization: Prevention in pregnant and postpartum patients. Uptodate. Accessed 2/4/21
  2. ACOG practice bulletin. Prevention of Rh D alloimmunization. Number 4, May 1999 (replaces educational bulletin Number 147, October 1990). Clinical management guidelines for obstetrician-gynecologists. American College of Obstetrics and Gynecology. Int J Gynaecol Obstet. 1999; 66(1):63-70. [PubMed 10458556]
  3. Miraflor, E, et al. Emergency uncrossmatched transfusion effect on blood type alloantibodies. J Trauma. 2012; 72:48-53.