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Omalizumab

Generic Name: omalizumab (OH ma LIZ oo mab)
Brand Name: Xolair, Xolair Prefilled Syringe

Medically reviewed by Drugs.com on May 29, 2019 – Written by Cerner Multum

What is omalizumab?

Omalizumab is used to treat moderate to severe asthma that is caused by allergies in adults and children who are at least 6 years old. Omalizumab is used when asthma symptoms are not controlled by asthma inhaled steroid medicine. Omalizumab is not a rescue medicine for treating an asthma attack.

Omalizumab is also used to treat chronic hives (idiopathic urticaria) in adults and children who are at least 12 years old, after antihistamines have been tried without success.

Omalizumab is not for use in treating other allergies, rashes, or attacks of bronchospasm.

Omalizumab may also be used for purposes not listed in this medication guide.

Important Information

Some people using omalizumab have had a severe, life-threatening allergic reaction either right after the injection or hours later. An allergic reaction may occur even after using omalizumab regularly for a year or longer.

Get emergency medical help if you have signs of an allergic reaction: hives, itching; anxiety or fear; flushing (warmth, redness, or tingly feeling); feeling like you might pass out; chest tightness, wheezing, cough, feeling short of breath, difficult breathing; fast or weak heartbeats; swelling of your face, lips, tongue, or throat.

Before taking this medicine

You should not use omalizumab if you are allergic to it.

Tell your doctor if you have any signs of infection (fever, swollen glands, general ill feeling), or if you have ever had:

  • any other allergies (foods, pollens, etc);

  • allergy shots;

  • a severe allergic reaction (anaphylaxis);

  • an infection caused by parasites (such as giardia, malaria, leishmaniasis, hookworm, pinworm, toxoplasmosis, and many others);

  • a heart attack or stroke;

  • cancer; or

  • a latex allergy.

Using omalizumab may increase your risk of certain types of cancers of the breast, skin, prostate, or salivary gland. Talk to your doctor about your individual risk.

While you are using omalizumab, you may also have an increased risk of becoming infected with parasites (worms) if you live in or travel to areas where such infections are common. Talk with your doctor about what to look for and how to treat this condition.

Some babies born to mothers using omalizumab during pregnancy had low birth weight. However, it is not known whether this was due to omalizumab use or to severe asthma in the mothers. The benefit of treating asthma may outweigh any risks to the baby. Tell your doctor if you are pregnant.

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of omalizumab on the baby.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

How is omalizumab given?

Your doctor may perform an allergy skin test or blood test to make sure this medicine is right for you.

Omalizumab is injected under the skin. A healthcare provider will give you this injection every 2 or 4 weeks.

Your condition may not improve right away. For best results, keep receiving omalizumab as directed. Talk with your doctor if your symptoms do not improve after a few weeks of treatment.

Omalizumab doses are based on weight. Your dose needs may change if you gain or lose weight.

If you also use a steroid medication, you should not stop using it suddenly. Follow your doctor's instructions about tapering your dose.

Seek medical attention if your breathing problems get worse quickly, or if you think your asthma medications are not working as well.

You may need frequent medical tests, such as allergy tests and lung function tests. Your stools may also need to be checked for parasites, especially if you travel.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your omalizumab injection.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using omalizumab?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Omalizumab side effects

Some people using omalizumab have had a severe, life-threatening allergic reaction either right after the injection or hours later. Allergic reaction may occur even after using the medication regularly for a year or longer.

You will be watched closely for a short time after each injection, to make sure you do not have an allergic reaction to omalizumab.

Get emergency medical help if you have signs of an allergic reaction:

  • hives, itching;

  • anxiety or fear, feeling like you might pass out;

  • flushing (warmth, redness, or tingly feeling);

  • chest tightness, wheezing, cough, feeling short of breath, difficult breathing;

  • fast or weak heartbeats; or

  • swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • trouble breathing;

  • numbness or tingling in your arms or legs;

  • fever, muscle pain, and rash within a few days after receiving an injection;

  • heart attack symptoms--chest pain or pressure, pain spreading to your jaw or shoulder; or

  • signs of a blood clot--sudden numbness or weakness, problems with vision or speech, coughing up blood, swelling or redness in an arm or leg.

Common side effects may include:

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.

What other drugs will affect omalizumab?

Other drugs may affect omalizumab, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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