VariZIG Side Effects Center

Last updated on RxList: 9/5/2019
VariZIG Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

Last reviewed on RxList 9/5/2019

VariZIG [Varicella Zoster Immune Globulin (Human)] is an immune serum used to reduce, prevent, or decrease the severity of chicken pox (varicella zoster virus) infections in high-risk people. People most at-risk include children and adults with weak immune systems, pregnant women, and infants. Common side effects of VariZIG are usually mild and include:

  • injection site pain,
  • chills,
  • fever,
  • headaches,
  • vomiting,
  • nausea,
  • joint pain,
  • fatigue,
  • hives, and
  • itching and rash.

VariZIG is an injection and is available as in single use 6 mL glass vials. A patient may be administered up to 5 vials depending on body weight. VariZIG may be administered either intravenously or intramuscularly. VariZIG should not be used in patients with a history of allergic reactions to blood products or patients deficient in a blood protein called IgA. VariZIG is not known to interact with other drugs. Tell your doctor all medications and supplements you use. VariZIG should be given to pregnant women only if clearly needed. It is unknown if VariZIG passes into breast milk. Consult your doctor before breastfeeding.

Our VariZIG [Varicella Zoster Immune Globulin (Human)] Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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VariZIG Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • signs of a blood clot in the brain--sudden numbness or weakness (especially on one side of the body), slurred speech, problems with vision or balance;
  • signs of a blood clot in the heart or lung--chest pain, rapid heart rate, sudden cough, wheezing, rapid breathing, coughing up blood;
  • signs of a blood clot in your leg--pain, swelling, warmth, or redness in one or both legs; or
  • signs of a new infection--fever, chills, flu symptoms, mouth sores, pain when swallowing.

Side effects may be more likely in older adults.

Common side effects may include:

  • headache; or
  • pain where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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VariZIG Professional Information


The most serious adverse drug reactions observed in clinical trials for all subjects and patients (n=601) include pyrexia, nausea, and vomiting.

The most common adverse drug reactions (reported by ≥ 1% of subjects) observed in clinical trials for all subjects and patients (n=601) are the following:

  • injection site pain (3%),
  • headache (2%),
  • rash (including terms pruritus, rash, rash erythematous, rash vesicular and urticaria) (1%),
  • fatigue (1%),
  • chills (1%),
  • nausea (1%).

All other adverse drug reactions occurred in less than 1%.

Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Six hundred and one (n=601) high risk individuals received VARIZIG intramuscularly in two clinical trials which included pregnant women, infants and immunocompromised pediatric and adult patients. The highest incidence of adverse reactions occurred in pregnant women (n=166), including injection site pain (7%), rash (including terms pruritus, rash, rash erythematous, and rash vesicular) (4%), headache (3%), and fatigue (2%). All other adverse reactions occurred in 1% or less of clinical trial subjects within each high risk group. A single incidence of serum sickness (approximately one in 600 patients treated with VARIZIG) was observed in an immunocompromised adolescent patient.

There were eight reported adverse events associated with the coagulation system including, deep vein thrombosis (n=1), disseminated intravascular coagulation (n=1) , intracranial hemorrhage (n=2), coagulopathy (n=2), intraventricular hemorrhage (n=1), and pulmonary hemorrhage (n=1) in 621 subjects in the open-label, Expanded Access Protocol (EAP); the study was not designed to differentiate between adverse events attributed to the underlying medical condition and adverse reactions to VARIZIG.

Read the entire FDA prescribing information for VariZIG (Varicella Zoster Immune Globulin (Human) for Injection)


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© VariZIG Patient Information is supplied by Cerner Multum, Inc. and VariZIG Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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