Hizentra (immune globulin subcutaneous [human], 20% liquid) is a prescription drug approved to treat certain conditions that affect the immune system. Hizentra comes as a liquid solution given as an injection under the skin.

Specifically, Hizentra is used to treat:

To learn more about Hizentra’s uses, see the “Uses for Hizentra” section.

Hizentra basics

Hizentra is a biologic medication. A biologic is made from parts of living organisms. It’s available only as a brand-name drug. It isn’t available in a biosimilar form.

Biosimilars are like generic drugs. Just as generic drugs can be an alternative to brand-name medications, biosimilars are an effective alternative to biologics.

Biosimilars will have the same active ingredient core name as the brand-name drug, but with unique suffixes. This is why “-abcd” appears at the end of the name of the active ingredient. This is to show it’s distinct from biosimilars that may be created in the future.

Hizentra has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Precautions” section.

Hizentra is used to treat:

  • primary immunodeficiency (PI) in adults and children ages 2 years and older
  • chronic inflammatory demyelinating polyneuropathy (CIDP) in adults

PI refers to a group of inherited conditions, such as Wiskott-Aldrich syndrome, that weaken the immune system. These conditions increase the risk of infections. They may cause symptoms such as fatigue (low energy) or loss of appetite.

CIDP is a condition where the immune system mistakenly attacks the protective covering of the nerves. This can cause nerve damage and inflammation, usually in the arms and legs. Symptoms of CIDP may include pain and tingling, or numbness in the arms or legs.

Like most drugs, Hizentra may cause mild to serious side effects. The following lists contain some of the more common side effects Hizentra may cause, but they don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you take

Your doctor or pharmacist can tell you more about the potential side effects of Hizentra. They can also suggest ways to help reduce side effects.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while taking Hizentra and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

Mild side effects

Here’s a list of some of the mild side effects that Hizentra can cause. To learn about other mild side effects, talk with your doctor or pharmacist, or read Hizentra’s prescribing information.

Mild side effects of Hizentra that have been reported include:

  • pain or swelling near the infusion site
  • headache
  • diarrhea
  • fatigue (low energy)
  • pain in your arms, legs, back, or joints
  • nausea and vomiting
  • cough
  • upper respiratory infection, such as the common cold
  • skin rash
  • itching
  • upper abdominal pain
  • migraine
  • falls

Mild side effects of many drugs may go away within a few days to a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Hizentra can occur, but they aren’t common. If you have serious side effects from Hizentra, call your doctor right away. If you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of Hizentra that have been reported include:

For more information about side effects related to boxed warnings, see the “Precautions” section.

Allergic reaction

For some people, Hizentra can cause an allergic reaction.

In general, symptoms of an allergic reaction can be mild or serious.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should continue Hizentra treatment.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Hizentra, they may have you switch to a different treatment.

The Hizentra dosage your doctor prescribes will depend on several factors. These include:

  • the type and severity of the condition you’re using Hizentra to treat
  • your body weight in kilograms (kg)
  • your blood immunoglobulin G (IgG) levels
  • other medications you are taking
  • whether you have an increased risk of being exposed to measles

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Forms and strength

Hizentra is available as a liquid solution in prefilled, single-use syringes and vials that’s given as an injection under your skin. It’s available in one strength of 0.2 grams of IgG per milliliter (0.2 g/mL) of solution.

Recommended dosages

Your doctor will prescribe the dosage of Hizentra that’s right for you. Keep reading to learn more.

Dosage for primary immunodeficiency (PI)

For treatment of PI, your starting dosage depends on whether you are switching from one of the following treatments:

  • an injection under the skin immunoglobulin (IgSC) treatment, such as Cuvitru, Xembify, or Hyqvia
  • an intravenous immunoglobulin (IVIg) treatment, such as Gammagard, Privigen, or Panzyga

If you’re switching from IgSC, you’ll likely continue with the same weekly dose. But if you’re switching from IVIg, your doctor will convert your IVIg dose into a starting weekly dose of Hizentra. You’ll usually start Hizentra at least 1 week after your last dose of IVIg or IgSC.

Your doctor will recommend how often to use Hizentra. It could range from using the drug daily, a few times per week, once per week, or every 2 weeks.

Based on how well the treatment is working and your IgG levels, your doctor may adjust your Hizentra dosage over time.

Dosage for chronic inflammatory demyelinating polyneuropathy (CIDP)

For CIDP, the starting dose of Hizentra is based on your body weight in kg. The typical starting dose is 0.2 g per kg of body weight each week. (One kg is about 2.2 pounds [lb].) For example, a person who weighs 60 kg (about 132 pounds) would receive 12 g of Hizentra per week.

You’ll usually start Hizentra at least 1 week after your last dose of IVIg.

If needed, your doctor may increase your dose to 0.4 g per kg of body weight each week. If your condition does not improve at this higher dose, your doctor may recommend stopping Hizentra and restarting IVIg treatment.

Each weekly dose of Hizentra can be given in one session or split into two sessions over 1 or 2 days.

Children’s dosage

Hizentra is used to treat PI in children ages 2 years and older. It’s not approved for CIDP in children.

The dosage of Hizentra for PI in children is the same as for adults. For details, see the “Dosage for primary immunodeficiency (PI)” section.

How to use

Hizentra is available as a liquid solution that’s given as an injection under your skin. You’ll use Hizentra with an infusion pump. Your doctor or another healthcare professional will show you how to give yourself these injections at home.

Each infusion may take 1 to 2 hours, depending on your dose and how many infusion sites you use. Examples of common infusion sites include the abdomen, thigh, upper arm, or side of the outer hip.

Talk with your doctor if you have other questions about using Hizentra. You can also visit the drug manufacturer’s website for PI or CIDP.

About using Hizentra

The following are some common questions about using Hizentra.

  • What if I miss a dose of Hizentra? If you miss a dose of Hizentra, talk with your doctor or pharmacist. They can advise you on whether to take a missed dose or skip it. The manufacturer of Hizentra hasn’t provided recommendations for what to do about a missed dose.
  • Will I need to use Hizentra long term? Hizentra is typically used as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely use it long term.
  • How long does Hizentra take to work? Hizentra begins to work after you take your first dose. But you likely won’t feel the drug working in your body. Your doctor will order tests throughout your treatment to check whether Hizentra is working to treat your condition.

Overdose

Call your doctor if you think you’ve used too much Hizentra. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 or your local emergency number. Or go to the nearest emergency room.

Hizentra is not known to interact with other medications, herbs, supplements, foods, or alcohol. The manufacturer did not list any of these interactions in the drug’s prescribing information.

But this doesn’t mean that these interactions won’t exist in the future. For example, new drugs could be approved that interact with Hizentra.

Before taking Hizentra, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also, tell them about any vitamins, herbs, or supplements you use. Sharing this information can help you avoid potential interactions.

Interactions with vaccines and lab tests

Here is a list of vaccines and lab tests that can interact with Hizentra. This list does not contain all factors that may interact with Hizentra. If you have questions about interactions that may affect you, ask your doctor or pharmacist.

Hizentra and alcohol

Alcohol is not known to interact with Hizentra.

Talk with your doctor to determine whether it’s safe for you to consume alcohol during Hizentra treatment.

Whether you have health insurance or not, cost may be a factor when you’re considering Hizentra. What you’ll pay for Hizentra may depend on several things, such as your treatment plan and the pharmacy you use.

If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. A program called Hizentra Connect may also be available.

The following is important information to consider and discuss with your doctor or pharmacist before taking/using Hizentra.

Pregnancy and Hizentra

It’s not known whether Hizentra is safe to use during pregnancy. If you’re planning a pregnancy or can become pregnant, talk with your doctor before using this drug.

Hizentra and breastfeeding

It’s not known whether Hizentra should be used while breastfeeding. If you’re currently breastfeeding or planning to do so, talk with your doctor before using this drug.

This section describes the warnings and precautions for Hizentra.

FDA warning: Risk of blood clots

Hizentra has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA) about drug effects that may be dangerous.

Using Hizentra may increase the risk of blood clots. But this side effect was not reported in the drug’s studies. However, blood clots are a known risk of immunoglobulin treatments. (Hizentra is a type of immune globulin.)

Symptoms of a blood clot may include:

  • pain or swelling in the affected area
  • skin warmth
  • difficulty breathing

Certain factors may increase the risk of blood clots with Hizentra. Examples include older age, immobility for long periods of time, and history of blood clots.

If you have symptoms of a blood clot during Hizentra treatment, contact your doctor right away. But if your symptoms seem life threatening, call 911 or a local emergency number immediately.

Other precautions

Before taking Hizentra, discuss your health history with your doctor. Hizentra may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

Note: For more information about the potential negative effects of Hizentra, see the “Side effects of Hizentra” section.

Here are answers to some commonly asked questions about Hizentra’s side effects.

How long does Hizentra stay in your system?

The exact amount of time Hizentra stays in your body can vary depending on certain factors. Examples include your dose, how often you use the drug, and how quickly your body breaks it down.

After your last dose, it may take several weeks for Hizentra to fully leave your system.

Talk with your doctor or pharmacist if you have other questions about how long Hizentra stays in your system.

Does Hizentra cause long-term side effects?

It’s possible. Long-term side effects include those that may start at any time you’re taking a drug, even if you’ve taken it for a long time. It also includes side effects that may not go away, even after you stop taking the drug.

Examples of long-term side effects reported in Hizentra’s studies include:

  • aseptic meningitis (swelling around the brain and spinal cord)
  • lung damage

Talk with your doctor to learn more about possible side effects of Hizentra and how long they may last.

Other drugs are available that can treat your condition. If you’d like to explore an alternative to Hizentra, talk with your doctor. They can tell you about other medications that might work well for you.

The following drugs are similar to Hizentra:

  • an injection given under the skin immune globulin (IgSC), such as Cuvitru, Xembify, and Hyqvia
  • IV immune globulin (IVIg), such as Gammagard, Privigen, and Panzyga

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.