Xolair®, or omalizumab, is an injection used to reduce asthma attacks triggered by allergens such as pollen. It is in the drug class called monoclonal antibodies, which block the actions of natural substances in the body that contribute to asthma attacks. Doctors typically give patients an injection under the skin every two or four weeks at their office. Xolair® can cause life-threatening allergic reactions and increase the risk of certain cancers and parasitic infections.
Patients 12 years old and older who experience persistent and moderate to severe asthma attacks after inhaling allergens such as dust mites, pet dander or pollen, can ask their doctor about taking Xolair® if steroid inhalers aren't helping their condition. The injections prevent immunoglobulin E, or IgE, in the body from triggering asthma attacks. Although Xolair® can lower the number of attacks a patient suffers, it can't be used to stop an attack that's already started.
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Doctors mix Xolair® powder into a liquid form and administer up to three injections to patients every other week or once a month, depending on the severity of the patient's condition. Patients should remain at the doctor's office for awhile after an injection to be monitored for a serious allergic reaction, although these reactions can also occur several hours later. Signs of an allergy to Xolair® include hives, wheezing, trouble breathing, fast or slow pulse, anxiety, swollen tongue or throat and dizziness. Allergic reactions can happen even if the patient has been receiving injections for a long time without any complications.
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Taking Xolair® can lead to a higher risk of prostate, breast, skin and parotid cancer, as well as hookworm, roundworm or whipworm infections in geographical areas where these parasites are common. Patients should discuss these risks with their doctor before starting injections and also let their doctor know if they're allergic to any medications. Doctors should also know if patients are pregnant or breastfeeding, receiving other allergy shots or taking any other prescription or over-the-counter medications.
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Xolair® can cause temporary and mild side effects including ear pain, joint pain, drowsiness, headache, hair loss, itching and stinging or redness at the injection site. Other side effects include upper respiratory infections, viral infections and sinusitis. If any of these symptoms or conditions are prolonged or become severe, patients should let their doctors know.