varicella zoster immune globulin, human

Action and Spectrum

Actions and Spectrum: 

Actions: 

• Passive Immunization: VZIG provides passive immunity to individuals exposed to VZV but not yet immune or have a weakened immune system. It contains specific antibodies against the virus, which can help the body fight off the infection or reduce its severity. 
• Neutralization of Virus: The antibodies present in VZIG can neutralize the varicella-zoster virus, preventing it from infecting susceptible cells and spreading within the body. 
• Short-term Protection: VZIG provides temporary protection and is effective for a limited period, usually a few weeks. It does not confer long-term immunity to the varicella-zoster virus. 

Spectrum: 

• Immunocompromised individuals: Those with weakened immune systems due to diseases like HIV/AIDS, leukemia or undergoing immunosuppressive treatments (e.g., organ transplant recipients). 
• Pregnant women: If a pregnant woman has not had chickenpox or has been vaccinated by the chickenpox vaccine and is exposed to the virus, VZIG may be administered to reduce the risk of severe complications for the mother and the unborn child. 
• Newborn infants: Infants born to mothers with chickenpox shortly before or after delivery may be given VZIG to prevent severe infection, particularly if the mother did not have immunity before pregnancy. 

Drug Interaction

Adverse Reaction

Frequency defined 

1-10% 

Headache (2%) 

Pain at the injection site (2%) 

Frequency not defined 

Chills 

Nausea 

Thrombosis 

Fatigue 

Rash 

Black Box Warning

Black Box Warning: 

None 

Contraindication / Caution

Contraindication/Caution: 

Contraindications: 

• Known severe allergic reaction 
• History of severe allergic reaction to human immunoglobulin 
• Acute active infection 

Caution: 

• Previous mild allergic reaction 
• Pregnancy and breastfeeding 
• Blood disorders 
• Immunoglobulin A (IgA) deficiency 

Pregnancy / Lactation

Pregnancy consideration:  

Pregnancy Category: C 

Breastfeeding warnings:  

Unknown if the vaccine is excreted in breast milk. 

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester.        
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women        
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.       
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.        
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.        
• Category N: There is no data available for the drug under this category

Pharmacology

Pharmacology: 

varicella zoster immune globulin, human (VZIG), is a biological product derived from human plasma that contains antibodies against the varicella-zoster virus (VZV). The pharmacology of VZIG involves its mechanism of action, pharmacokinetics, and therapeutic uses. As a passive immunization product, VZIG provides temporary protection against VZV and is primarily used for high-risk individuals exposed to the virus. 

Pharmacodynamics: 

The pharmacodynamics of varicella zoster immune globulin, human, revolves around its ability to provide temporary passive immunity against VZV by neutralizing the virus and enhancing the body’s immune response. It is primarily used as a preventive measure for high-risk individuals exposed to VZV who may not have developed immunity or are at risk of severe complications. 

Pharmacokinetics: 

Absorption 

Peak plasma concentration is achieved in 4.5 days 

The peak plasma concentration is 136 mIU/mL 

The area under the curve is 2472-4087 mIU•day/mL (24-84 days) 

Distribution 

VZIG contains specific antibodies against the varicella-zoster virus (VZV). Once absorbed into the bloodstream, these antibodies are distributed throughout the body, allowing them to reach various tissues and organs. The distribution of VZIG follows the distribution of plasma and immunoglobulin components. 

Metabolism 

As a biological product derived from human plasma, VZIG does not undergo metabolism like small-molecule drugs. The antibodies in VZIG are natural protein molecules broken down and cleared from the body through physiological processes. 

Elimination and Excretion 

The half-life is 26.2 days 

The rate of total body clearance is 0.204 mL/day 

Adminstartion

Administration: 

The administration of varicella zoster immune globulin, human (VZIG), involves the intramuscular (IM) or intravenous (IV) injection of the product. VZIG should be administered as soon as possible after exposure to VZV to maximize its effectiveness.

The efficacy of VZIG decreases if administered more than 96 hours after exposure to the virus. After VZIG administration, patients should be monitored for adverse reactions or side effects. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: varicella zoster immune globulin human 

Pronounced: VAR-i-SEL-a-ZOS-ter-im-MUNE-GLOB-ue-lin  

Why do we use varicella zoster immune globulin human? 

varicella zoster immune globulin, human (VZIG), is used for passive immunization to provide temporary protection against the varicella-zoster virus (VZV). It contains specific antibodies against VZV, the virus responsible for causing chickenpox (varicella) and herpes zoster (shingles). VZIG is administered to high-risk individuals exposed to VZV who may not have developed immunity or are at risk of severe complications.