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Does Xolair cause weight gain?

Medically reviewed by Carmen Pope, BPharm. Last updated on Feb 23, 2024.

Official Answer by Drugs.com

There were no reports of weight gain or weight loss in clinical trials with Xolair.

Weight gain is more likely to be caused by corticosteroids, hydroxyzine, or antihistamines that may also be used to treat allergic asthma or hives.

Xolair (omalizumab) is an antibody that may be used to treat allergic asthma that is

Xolair is also approved to treat:

Xolair is administered by injection under the skin (subcutaneously) once every two to four weeks. The dosage of Xolair is based on body weight.

If your weight does change while taking Xolair, talk with your doctor who can recommend diet and exercise tips to encourage a healthy weight.

References

Read next

Is Xolair an immunosuppressant?

Xolair does act on the body’s immune system to prevent an allergic response, but because it only acts on the allergic arm of the immune system, it does not appear to compromise the immune system as other immunosuppressants do. Xolair is not like traditional immunosuppressants, such as prednisone or cyclosporine because it does not increase the risk of infection nor the risk of COVID-19. Continue reading

How long before Xolair starts working?

Free serum IgE levels are decreased within an hour of Xolair administration. However it may take several months for the full effects of Xolair to be seen, although some symptom improvement may be noted after a few weeks. Significant improvements were noted after 4 months in those with allergic asthma, after 3 months in those with chronic urticaria, and after 16 to 20 weeks in those with Ig-E-mediated food allergies. Continue reading

How does Xolair work?

Xolair works by preventing IgE from binding to IgE receptors on mast cells and basophils. This prevents mast cells and basophils from releasing histamine and heparin. Histamine narrows smooth muscle in the airways making it harder to breathe and also causes tissue swelling, itchy skin, hives, and other allergic-type symptoms. Heparin makes it harder for blood to clot. Continue reading

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