Varicella-zoster immune globulin (VZIG) provides passive immunity in individuals who are at a high risk of developing varicella infection after exposure or who may develop complications of the disease. Remember that varicella-zoster immune globulin (VZIG) only offers transient protection from varicella infection. Varicella vaccination should be given to achieve long-lasting immunity.

High-risk individuals who may develop varicella infection include:

• Immunocompromised children and adults. These include:
  • Primary or acquired immunodeficiency such as AIDS
  • Individuals receiving immunosuppressants and corticosteroids equivalent to 2 mg/kg or more or 20 mg/day or more.
  • Individuals with cancers especially hematological cancers such as leukemia and lymphomas.
• newborns of mothers with varicella infection within 5 days or 48 hours after delivery.
• premature infants who were exposed during the neonatal period including
  • all neonates less than 28 weeks of gestation regardless of maternal immunity
  • All newborns who were born after 28 weeks of pregnancy and who had no maternal immunity against varicella
• Adults without evidence of immunity, and
• pregnant women without evidence of immunity
• In individuals who have contraindications to the varicella vaccine.

Varicella-zoster immunoglobulin dose in Adults

(VZIG) Varicella-zoster immunoglobulin dose in the prophylaxis of Varicella infection:

• ≥40.1 kg:

  • 625 units Intramuscular as a single dose

Note:

• Within 96 hours of exposure to varicella infection and no later than 10 days at most, VZIG should be delivered.
• Hematopoietic transplant recipients and individuals who develop a rash after varicella vaccination should ideally receive the immunoglobulin within 48 hours and not later than 96 hours of exposure.

Varicella-zoster immune globulin (VZIG) dose in children:

Note:

• As soon as feasible following exposure to varicella, VZIG should be given.
• The exposed person should obtain the VZIG in the ideal scenario within 96 hours. Up to 10 days after exposure, it can be given.
• Patients undergoing hematopoietic transplants and those who get a rash after vaccination should receive VZIG within 48 and up to 96 hours of exposure.
• Patients at a higher risk of developing varicella infection, who had received VZIG 3 weeks or more of the exposure, should receive an additional full dose.
• The minimum and the maximum doses are 62.5 units and 625 units respectively.

VZIG dose in postexposure prophylaxis of varicella:

• Infants, Children, and Adolescents:

  • 2 kgs or less:

    • 62.5 units intramuscular.

  • 1 to 10 kg:

    • 125 units intramuscular.

  • 1 to 20 kg:

    • 250 units intramuscular.

  • 1 to 30 kg:

    • 375 units intramuscular.

  • 1 to 40 kg:

    • 500 units intramuscular.

  • >40 kg:

    • 625 units intramuscular.

VZIG vaccine in Pregnancy (Risk Factor C)

• Varicella infection during pregnancy can lead to intrauterine death.
• VZIG's safety is unknown when it is administered to pregnant women.
• It may be given to pregnant mothers, however, as the main purpose is to protect the mother and not the child from the infection.

Varicella-zoster immune globulin use during breastfeeding:

• Lactating women should use it with caution

Varicella-zoster immunoglobulin dose in Renal Disease:

• The manufacturer has not recommended any dose adjustment in patients with kidney disease.

Varicella-zoster immunoglobulin dose in Liver Disease:

• The manufacturer has not recommended any dose adjustment in patients with liver disease.

Side Effects of Varicella-zoster immune globulin:

• Central Nervous System:

  • Chills
  • Fatigue
  • Headache

• Dermatologic:

  • Skin Rash

• Gastrointestinal:

  • Nausea

• Local:

  • Pain at the site of Injection

Contraindication to Varicella-zoster immune globulin:

• Patients who have had severe allergic reactions to human immunoglobulins in the past
• Ig A deficiency
• Allergies to any component of this formulation
• Varicella-zoster is not a virus that affects patients.

Warnings and precautions

• Hypersensitivity reactions
  • It is possible to have severe allergic reactions.
  • Immunoglobulin therapy must be discontinued immediately if any allergic reactions are noted and the patient should be treated immediately (with epinephrine).
  • Hypersensitivity reactions are more common in patients who have low IgA levels.
• Thrombotic events
  • Immunoglobulins may raise the risk of thrombosis.
  • Patients who are at a high risk for thrombotic events should be told to stop using the medication.
• The following patients are at high risk for thrombosis:
  • People with multiple cardiovascular risk factors
  • Patients with dementia
  • Patients suffering from atherosclerotic diseases
  • People with reduced cardiac output
  • Patients who are hypercoagulable
  • Long-term immobilization
  • Patients with hyperviscosity conditions.
  • Patients at high risk, such as those with cancer, may have their blood viscosity measured before initiating therapy.
  • Cryoglobulinemia patients
  • High levels of triglyceride
  • Raise fasting chylomicrons e
  • Multiple myeloma patients or Waldenstrom's maglobulinemia.
• Bleeding disorders:
  • Patients with coagulopathy or thrombocytopenia should avoid intramuscular administration.

Varicella-zoster immune globulin (human): Drug Interaction

Monitor:

• Features of active varicella infection should be monitored for up to 28 days after the administration of the immunoglobulins.
• In patients who are at risk for hyperviscosity, measure blood viscosity.

How to administer Varicella-zoster immune globulin?

• Immunoglobulin for varicella-zoster is injected intramuscularly into the upper thigh or deltoid muscle.
• The injection is brought to room temperature prior to use and injected into two or more separate sites. Administration into the deltoid is the preferred site of administration.
• Due to the possibility of damaging the sciatic nerve, the gluteal region should be avoided.
• If the injection is to be administered in the thigh, the upper and outer quadrant should be used. Per injection, no more than 3 ml should be administered.

Mechanism of action of Varicella-zoster immune globulin:

• Humans develop antibodies in the form of varicella virus immune globulins.
• Human plasma with high levels of antibodies is obtained from patients who have recovered from the disease.
• The protection against Varicella-zoster immuneglobulin is effective for 6 weeks It is mThe reticuloendothelial systems were etabolized.

Bioavailability is100%

Half-life eliminationAfter intravenous administration, it takes 18-24 days. Intramuscular administration takes 22-30 days.

When plasma concentration reaches its peakIt is less than three hours after intravenous administration, and 4.5 +-2.8 days after intramuscular administer.

International Brands of Varicella-zoster immune globulin:

• VariQuin
• Varitect
• Varitect-CP
• Vazigam

Varicella-zoster immunoglobulin Brands in Pakistan:

 No Brands Available in Pakistan.