Varicella (chickenpox)

Varicella (chickenpox) is a highly infectious disease caused by the varicella-zoster virus (VZV). Secondary attack rates for this virus might reach 90% for susceptible household contacts. VZV causes a systemic infection that results typically in lifetime immunity. In otherwise healthy persons, clinical illness after re-exposure is rare.1

The following patient groups are at risk for severe disease and complications from varicella and should receive postexposure prophylaxis with VZIG2

Immunocompromised patients without evidence of immunity to varicella

Neonates whose mothers have signs and symptoms of varicella around the time of delivery

Premature neonates exposed postnatally

Pregnant women without evidence of immunity to varicella

Postexposure prophylaxis with GamaSTAN® (immune globulin [human])2

The CDC recommends varicella-zoster immune globulin (VZIG) for postexposure prophylaxis of varicella for persons at high risk for severe disease who lack evidence of immunity to varicella. GamaSTAN may be used to attempt to modify varicella in susceptible high-risk individuals when VZIG is not available.3

Dosing Recommendations3




0.6 to 1.2 mL/kg


Administer promptly only if VZIG is unavailable

Varicella Dosage Instructions


0.6 to 1.2 mL/kg

Administer promptly only if VZIG is unavailable

For patients at risk of thrombosis, do not exceed the recommended dose of GamaSTAN. GamaSTAN is not indicated for routine prophylaxis or treatment of rubella, poliomyelitis, mumps, or varicella.

Have a question about GamaSTAN immune globulin (human)?

Submit a request to get in contact with a representative.

Important Safety Information for GamaSTAN® (immune globulin [human])


GamaSTAN (immune globulin [human]) is indicated for prophylaxis following exposure to hepatitis A infection, prevention or modification of measles in susceptible persons exposed fewer than 6 days previously, modification of varicella, and modification of rubella in exposed women who will not consider a therapeutic abortion.

Limitations of Use

GAMASTAN is not indicated for routine prophylaxis or treatment of viral hepapitis type B, rubella, poliomyelitis, mumps, or varicella.


Thrombosis may occur with immune globulin products, including GamaSTAN. Risk factors may include: advanced age, prolonged immobilization, hypercoagulable conditions, history of venous or arterial thrombosis, use of estrogens, indwelling central vascular catheters, hyperviscosity, and cardiovascular risk factors. Thrombosis may occur in the absence of known risk factors.

For patients at risk of thrombosis, do not exceed the recommended dose of GamaSTAN. Ensure adequate hydration in patients before administration. Monitor for signs and symptoms of thrombosis and assess blood viscosity in patients at risk for hyperviscosity.

GamaSTAN is contraindicated in patients who have had anaphylactic or severe systemic hypersensitivity reactions to immune globulin (human) and in IgA-deficient patients with antibodies against IgA and a history of hypersensitivity.

Administer GamaSTAN cautiously to patients with a history of prior systemic allergic reactions following the administration of human immunoglobulin preparations. Have epinephrine available for treatment of acute allergic symptoms, should they occur.

Inject intramuscularly only. Do not administer GamaSTAN intravenously because of the potential for serious reactions (eg, renal dysfunction/failure/hemolysis, transfusion-related acute lung injury [TRALI]). Do not inject into a blood vessel.

GamaSTAN is made from human blood; it may carry a risk of transmitting infectious agents, eg, viruses, the variant Creutzfeldt-Jakob disease (vCJD) agent, and, theoretically, the Creutzfeldt-Jakob disease (CJD) agent.

The most common adverse reaction reported for GamaSTAN S/D during post-approval use was fatigue.

Antibodies in GamaSTAN may interfere with the response to live virus vaccines such as measles, mumps, polio, rubella, and varicella. Defer live vaccine administration for up to 6 months after GamaSTAN administration.

Please see full Prescribing Information for GamaSTAN.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088.


  1. Marin M, Güris D, Chaves SS, Schmid S, Seward JF; Advisory Committee on Immunization Practices (ACIP). Prevention of varicella: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2007;56(RR-04):1-40.
  2. Chickenpox (varicella). Centers for Disease Control and Prevention. Updated October 21, 2022. Accessed June 10, 2023.
  3. GamaSTAN® (immune globulin [human]) Prescribing Information. Grifols.