Xolair (omalizumab) is a prescription drug used to treat chronic (ongoing) hives without a known cause. Xolair is a biologic drug and does not come in a biosimilar version. It’s used when symptoms haven’t eased after certain antihistamine treatments.

Xolair comes in several forms that are injected under your skin.

The active ingredient in Xolair is omalizumab, which is a biologic. Xolair belongs to a group of drugs called monoclonal antibodies. To learn more about Xolair and its other uses, see this in-depth article.

Xolair has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “What should I know before using Xolair?” section.

What are chronic hives?

Chronic (ongoing) hives are raised, itchy bumps on your skin that come back often for at least 6 weeks.

What are the symptoms of chronic hives?

Symptoms of chronic hives include discolored or darkened areas of skin that may be swollen, itchy, or painful. These symptoms can appear on various areas of your body. Hives can also change shape, grow, and spread.

Who is Xolair prescribed for?

Doctors prescribe Xolair to treat chronic hives that do not have a known cause. It’s used for adults and children ages 12 years and older when their symptoms haven’t eased after certain antihistamine treatments, such as hydroxyzine (Vistaril), cetirizine (Zyrtec), and loratadine (Claritin).

Doctors typically will not prescribe Xolair to treat other types of hives.

How does Xolair treat chronic hives?

Xolair is approved to treat chronic hives in adults and children ages 12 years and older. The drug is prescribed when symptoms of this condition haven’t eased after certain antihistamine treatments.

Keep reading to learn how Xolair works.

How does Xolair work?

Xolair works by attaching to a protein in your body called immunoglobulin E (IgE). This protein activates specific cells in your immune system, leading to the release of substances that cause hives.

By attaching to IgE, Xolair reduces the activation of these immune system cells. As a result, the drug helps stop the release of substances that cause hives.

Is Xolair used in children?

Xolair is approved for use in children ages 12 years and older.

How effective is Xolair?

Xolair has been shown to be an effective treatment for chronic hives. In studies, most people had reduced hives and itching after 12 weeks of Xolair treatment.

To find out more about how Xolair performed in these studies, see the manufacturer’s website. You can also view Xolair’s prescribing information or talk with your doctor.

How is Xolair used?

Below are common dosages of Xolair when used for treating chronic hives. But be sure to follow the instructions and dosage your doctor has prescribed.

What is the usual dosage for Xolair?

For chronic hives, the usual dosage of Xolair is 150 milligrams (mg) or 300 mg every 4 weeks.

Note: Xolair has other uses in addition to treating chronic hives. The dosage may be different for these other uses. To learn more, see this article about Xolair’s dosage or talk with your doctor.

How do you use Xolair?

Xolair comes in several forms that are injected under your skin. These forms include:

• liquid solution in a single-use, prefilled syringe or autoinjector
• powder in a single-use vial, which a healthcare professional uses to form a liquid solution

You’ll inject Xolair under the skin of your thigh or abdomen, or a caregiver can inject the drug under the skin of your outer upper arm.

Xolair has a boxed warning for the risk of anaphylaxis. (For details, see the “What should I know before using Xolair?” section.) For this reason, a healthcare professional will give you the first three doses of Xolair. They’ll also advise you on when it’s safe for you or a caregiver to inject Xolair at home.

If you have questions about using Xolair, talk with your doctor or pharmacist. You can also view instructions on the manufacturer’s website.

How often should I use Xolair?

You’ll receive Xolair once every 4 weeks for chronic hives.

What are the side effects of Xolair?

Using Xolair for chronic hives* may cause side effects in some people. These side effects can be mild or serious.

The lists below include some of the main side effects that have been reported in people using Xolair. For information about other possible side effects of the drug, talk with your doctor or pharmacist.

You can also learn more from the side effect article on Xolair or from the drug’s prescribing information.

* Xolair is also approved to treat other conditions. It’s important to note that side effects from Xolair may differ depending on the condition it’s being used to treat.

What are Xolair’s mild side effects?

Xolair may cause mild side effects in some people. These include:

• cough
• headache
• injection site reactions, including skin discoloration, swelling, and pain
• joint pain
• mild infections, such as sinus infection and the common cold
• nausea

In many cases, mild side effects from the drug can be temporary. Some side effects may be easy to manage too. But if side effects last longer, bother you, or become severe, talk with your doctor or pharmacist.

What are Xolair’s serious side effects?

Using Xolair may lead to rare but serious side effects. Examples include:

• cancer, including prostate cancer, breast cancer, and skin cancer
• combined symptoms of skin rash, fever, and joint pain, usually within 5 days of your first Xolair injection
• parasitic infection, such as hookworm
• boxed warning: anaphylaxis (See the “What should I know before using Xolair?” section.)

Call your doctor right away if you have any serious side effects while using Xolair. If the side effects seem life threatening or if you think you’re having a medical emergency, call 911 or your local emergency number immediately.

Allergic reaction

For some people, Xolair can cause an allergic reaction. In fact, Xolair has a boxed warning for the risk of a severe and possibly life threatening allergic reaction called anaphylaxis. For details, see the “What should I know before using Xolair?” section.

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 Xolair treatment.

If you have symptoms of a severe allergic reaction, such as swelling or trouble 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 Xolair, they may have you switch to a different treatment.

What should I know before using Xolair?

Before you use Xolair, there’s some important information to keep in mind. The drug may not be a safe option for you if you have certain medical conditions or other factors that affect your health. Some of these are mentioned below.

Boxed warning: Anaphylaxis

This drug has a boxed warning. This is the most serious warning from the FDA. A boxed warning alerts doctors and patients about drug effects that may be dangerous.

In rare cases, using Xolair may cause a severe and possibly life threatening allergic reaction called anaphylaxis. With anaphylaxis, you may have symptoms such as:

• low blood pressure
• fainting
• hives
• swelling of your tongue and throat

Anaphylaxis can happen after your first few doses of Xolair or with prolonged use, such as over a year.

Due to this risk, a healthcare professional will give you at least your first three doses of Xolair. This will allow them to closely monitor you for anaphylaxis. If you have any symptoms of this reaction, they’ll stop your Xolair treatment and manage the side effects.

Your healthcare professional will recommend when it’s safe for you or a caregiver to inject Xolair at home. If you have symptoms of this reaction while using Xolair at home, call 911 or your local emergency number right away.

If you have questions about this warning, talk with your doctor.

What other warnings should I know about?

In addition to boxed warnings, Xolair has other warnings. If any of the following medical conditions or other health factors apply to you, talk with your doctor before using Xolair:

• if you’ve had a parasitic infection
• if you’ve had cancer
• if you have sudden breathing problems or severe asthma attacks
• if you have a latex allergy
• if you’ve had an allergic reaction to the drug or any of its ingredients
• if you’re pregnant, breastfeeding, or considering either

Frequently Asked Questions (FAQs) about Xolair (Omalizumab)

What is Xolair?

Xolair (omalizumab) is a prescription biologic drug used to treat chronic (ongoing) hives without a known cause. It is typically prescribed when symptoms haven’t eased after certain antihistamine treatments. Xolair belongs to a group of drugs called monoclonal antibodies and does not come in a biosimilar version.

What are chronic hives?

Chronic hives are raised, itchy bumps on your skin that persist for at least 6 weeks and return frequently. Symptoms include discolored or darkened areas of skin that may be swollen, itchy, or painful. These symptoms can appear on various parts of the body and can change shape, grow, and spread.

Who is Xolair prescribed for?

Xolair is prescribed for adults and children aged 12 years and older who have chronic hives that do not have a known cause and whose symptoms haven’t eased after treatment with antihistamines like hydroxyzine (Vistaril), cetirizine (Zyrtec), and loratadine (Claritin). It is not typically prescribed for other types of hives.

How does Xolair work?

Xolair works by attaching to a protein in the body called immunoglobulin E (IgE). This protein activates specific cells in the immune system, leading to the release of substances that cause hives. By attaching to IgE, Xolair reduces the activation of these immune system cells, helping to stop the release of substances that cause hives.

How effective is Xolair?

Studies have shown that Xolair is an effective treatment for chronic hives, with most people experiencing reduced hives and itching after 12 weeks of treatment. For more detailed information, you can refer to the manufacturer’s website or consult Xolair’s prescribing information.

How is Xolair used?

What is the usual dosage for Xolair?

The usual dosage for treating chronic hives is 150 milligrams (mg) or 300 mg every 4 weeks. Note that Xolair may have different dosages for other conditions.

How do you use Xolair?

Xolair is injected under the skin, available in several forms including:

• Liquid solution in a single-use, prefilled syringe or autoinjector
• Powder in a single-use vial that a healthcare professional uses to prepare a liquid solution

The injection sites are the thigh, abdomen, or the outer upper arm (administered by a caregiver).

How often should I use Xolair?

Xolair is administered once every 4 weeks for chronic hives.

What are the side effects of Xolair?

What are Xolair’s mild side effects?

Common mild side effects include:

• Cough
• Headache
• Injection site reactions (discoloration, swelling, pain)
• Joint pain
• Mild infections (sinus infection, common cold)
• Nausea

What are Xolair’s serious side effects?

Serious side effects may include:

• Cancer (prostate, breast, skin)
• Combined symptoms of skin rash, fever, and joint pain
• Parasitic infections (e.g., hookworm)
• Boxed warning: Anaphylaxis

If you experience serious side effects, contact your doctor immediately. For life-threatening symptoms, call 911 or your local emergency number.

What should I know before using Xolair?

Boxed warning: Anaphylaxis

Xolair has a boxed warning for the risk of a severe and potentially life-threatening allergic reaction called anaphylaxis. Symptoms may include low blood pressure, fainting, hives, and swelling of the tongue and throat. Due to this risk, a healthcare professional will administer the first three doses and monitor for this reaction.

Other warnings

• History of parasitic infection
• History of cancer
• Sudden breathing problems or severe asthma attacks
• Latex allergy
• Previous allergic reaction to Xolair or its ingredients
• Pregnancy or breastfeeding

What if Xolair doesn’t work for hives?

If your symptoms haven’t eased after several weeks of treatment, consult your doctor. They may adjust your dosage or recommend alternative treatments.

How long does it take Xolair to start working for chronic hives?

Xolair starts to work after the first dose, but it may take several weeks to see a significant reduction in symptoms. Your doctor will monitor your progress during treatment.

How much does Xolair cost?

The cost of Xolair depends on factors like your treatment plan, insurance, pharmacy, and location. If administered by a healthcare professional, the cost of the appointment may also affect the price. Xolair is a brand-name biologic drug and is not available as a biosimilar.

Disclaimer: Always consult your doctor or another healthcare professional before taking any medication. This information is intended to be a helpful supplement to professional medical advice.

What if Xolair doesn’t work for hives?

If your chronic hives symptoms haven’t eased after several weeks of Xolair treatment, talk with your doctor. They can recommend what to do.

For example, they can tell you whether your Xolair dosage could be increased. Or they may recommend alternative treatment options for your condition.

If you have questions about what to expect when using Xolair, talk with your doctor.

How long does it take Xolair to start working for chronic hives?

Xolair starts to work after your first dose. But it may take several weeks for the drug to ease your symptoms. Your doctor will monitor your condition during your treatment to check whether the drug is working.

If you have other questions about what to expect from Xolair treatment for chronic hives, talk with your doctor.

Xolair cost

The price of Xolair depends on several factors. These can include your treatment plan, your insurance plan, the pharmacy you use, and your location. If you receive Xolair doses from a healthcare professional, the price may also depend on the cost of the appointment to receive the injection.

Xolair is a brand-name biologic drug. It’s not available as a biosimilar.

Disclaimer: adoctor 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.