All About Xolair (Omalizumab)

Side Effects of Xolair & More

(LifeWire) - Xolair (generic name omalizumab) is a medication used to treat allergic asthma. This medication acts on the body's immune system to decrease the allergic response to a trigger substance, such as pet dander, mites, dust or cockroach debris.

Who Can Benefit From Xolair?

People with moderate to severe asthma and those people whose asthma is largely related to allergies can usually benefit from Xolair. This prescribed medicine is only recommended secondary to other medicine(s). It is primarily used for people whose symptoms continue despite standard asthma treatments, such as high-dose inhaled corticosteroids and a long-acting beta-agonist.

In people with moderate to severe asthma with a large allergic component, Xolair has been shown to reduce severe asthma attacks and the number of emergency room visits. The drug is given by injection every two to four weeks, depending on the needs of the patient.

How Does Xolair Work?

Exactly how allergy-induced asthma develops is unclear, but it does seem to involve the immune system. When an irritant substance (trigger) is inhaled, the immune system in the airways activates an antibody response over time. This response causes inflammation or swelling of the breathing tubes, constriction of the surrounding muscles and extra mucus production. These changes cause standard asthma symptoms of difficulty in breathing, coughing, wheezing and chest tightness.

The drug interferes with this response by the body, and this stops the cascade of events that lead to the symptoms of asthma.

Side Effects of Xolair

Xolair can cause a rare but serious side effect called anaphylaxis. This is a severe allergic reaction that can be rapidly fatal if not treated appropriately and quickly. Only a small number of people (0.2%) who use this drug will ever experience an anaphylactic reaction, but this risk is serious enough that the drug must be given in a doctor's office. The patient may even need to be observed for a few hours after the first several injections.

Some people have allergic reactions to the drug many hours after, so anyone who is treated with Xolair should be given an Epi-Pen and instructions on how to use it. This prefilled syringe contains epinephrine, which is used in case of a severe allergic reaction.

Other side effects of the medication include discomfort at the injection site, skin redness and bumps. One finding of concern, though not yet completely understood, is that twice as many patients receiving this medication were found to have cancer when compared to a group of patients who received a placebo. Although the number of people in each group who had developed cancer were small, the types of cancer varied widely. At this time, it is unclear if there is a relationship between omalizumab injections and cancer.

Xolair is approved for use only in people 12 years of age and older. There have been no studies concerning the use of this medication in pregnancy. Therefore, any woman who is pregnant or trying to conceive should consult her doctor about using this medication.

Ask your doctor if Xolair might help if you have any of the following conditions:

• uncontrollable asthma
• allergies with uncontrollable asthma, despite regular use of appropriate medications
• controllable asthma, due to frequent use of steroid medication

Xolair can be prescribed by a primary care doctor. If your primary care doctor is not familiar with it, then a referral can be made to a doctor specializing in allergies or lung disease.

You can learn even more about Xolair (and other medicines), including how it might interact with other medications, at our Drugs A to Z page.

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