How Xolair (Omalizumab) Treats Chronic Spontaneous Urticaria
Xolair (omalizumab) is an injectable medicine approved for people with chronic spontaneous urticaria, which is hives that keep returning for 6 weeks or longer with no clear outside trigger. It is typically considered when antihistamines alone have not controlled symptoms. This guide explains how Xolair works, who it may help, what to expect, and what to ask your doctor.
What Is Xolair?
Xolair is a biologic medicine, a type of drug made from living cells that targets a specific part of the immune system. Originally developed for asthma, it was later approved for chronic spontaneous urticaria in people whose symptoms persist despite H1 antihistamine treatment. A lower-cost biosimilar version of omalizumab has also been approved in the U.S.
How Does Xolair Work for Hives?
Xolair binds to immunoglobulin E (IgE), an antibody involved in allergic reactions and in the activation of the skin cells (mast cells) that release histamine. By reducing free IgE, Xolair appears to calm those cells and reduce the release of histamine. Researchers do not fully understand why it works in chronic hives that are not clearly allergic, but it helps many people.
Who Is Xolair For?
Doctors usually consider Xolair for people who:
- Have chronic spontaneous urticaria (hives for 6 weeks or longer)
- Are old enough for the approved age group (adults and adolescents 12 and older)
- Still have symptoms despite taking an antihistamine, often at a higher-than-standard dose
Xolair is not a treatment for sudden, short-term hives, and it is not an emergency medicine for allergic reactions.
How Is Xolair Given?
Xolair is an injection under the skin, typically given about once every four weeks, with the dose set by your doctor. It is usually given in a doctor’s office at first so you can be monitored. In some cases, patients are later allowed to inject at home after training. You may continue taking your antihistamine alongside it.
How Well Does It Work?
In clinical studies, a substantial share of people with chronic spontaneous urticaria saw major improvement, and some became free of hives. Response varies. Some people improve within days to weeks, while others take a few months, and some do not respond. If hives return after stopping Xolair, many people respond again when treatment restarts.
Possible Side Effects
- Injection site reactions such as pain, swelling or redness
- Headache
- Sinus infections or colds
- Joint pain
- Rarely, a serious allergic reaction (anaphylaxis), which is why monitoring is recommended after early doses
Tell your doctor about all your medical conditions and medicines. Seek emergency help for any signs of a severe allergic reaction.
Cost and Insurance
Xolair is an expensive specialty medicine, and insurers usually require prior authorization and proof that antihistamines have been tried. A specialist’s office can often help with the paperwork and with manufacturer assistance programs.
Other Options for Chronic Hives
Xolair is one of several targeted options for chronic spontaneous urticaria. Others include dupilumab (Dupixent), an injection, and remibrutinib (Rhapsido), an oral tablet for adults, as well as cyclosporine in select cases. Which one fits you depends on age, health history, preferences and insurance. Learn more about chronic hives treatment, chronic spontaneous urticaria, and the stepwise approach in urticaria treatment.
Questions to Ask Your Doctor
- Is my urticaria the type that Xolair treats?
- Have I tried a high enough dose of antihistamine first?
- How long will it take to know if it is working?
- Can I inject at home, or will I need office visits?
- What happens if I stop?
Emergency Warning Signs
Go to the emergency room or call 911 immediately if hives are accompanied by difficulty breathing, wheezing, throat tightness, swelling of the lips, tongue or face, light-headedness or a sense that something is seriously wrong. These are warning signs of anaphylaxis.
Where to Get Evaluated
Deciding whether Xolair is right for you is a conversation for a specialist. The Hives Treatment Center in San Francisco, founded by Dr. Tiffany Young, offers online and in-person consultations for people with chronic hives.
Frequently Asked Questions
How long does it take for Xolair to work on hives?
Some people notice improvement within days to weeks. Others need a few months before the full effect appears.
Is Xolair a steroid?
No. Xolair is a biologic antibody medicine, not a steroid.
Can I stop Xolair once my hives clear?
Many people try stopping after a period of good control, with their doctor’s guidance. Hives may return, in which case treatment can be restarted.
Take the First Step
If chronic hives are not responding to antihistamines, you have more options than you may realize. Visit our hives treatment page to see the latest treatment options for your outbreak.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis or treatment. If you think you are having a medical emergency, call 911.
