OverviewDosageSide EffectsInteractionsHalf-Life

More than 330,000 individuals have received Xolair (omalizumab) injections since 2003. Considering how popular Xolair is right now, it pays to know a little bit more about this medication, including how long Xolair stays in your system.

Clinical studies have shown the following information regarding Xolair half-life:

Mean effective half-life: 24 days for those with CIU, 26 days for those with asthma

Time to steady-state: 12 weeks after a single-dose of 75-600 mg

Mean accumulation ratio: 1.1-1.4 from day 112 to day 336

Terminal phase half-life: 17 to 23 days

Xolair has an average bioavailability of 62 percent. Clinical studies show that it has a slow absorption in adults and adolescents with asthma with a peak serum concentration occurring at 7 to 8 days on average. This peak occurs at roughly the same time in patients with chronic hives. 

Free IgE serum levels dropped within an hour of the initial dose of Xolair. When multiple doses of Xolair were given to those with asthma, the serum concentration time-curve went up 6-fold compared to the first dose. In those with chronic hives, multiple doses led to proportional increases of omalizumab serum concentrations based on the dosage levels.


What is the half-life of Xolair?

The mean effective half-life of Xolair is 24 days for individuals who take it for chronic hives; the mean effective half-life for those who take this medication for asthma is 26 days. The terminal phase half-life for Xolair ranges from 17 to 23 days.

How long does Xolair stay in your system?

For individuals taking Xolair for asthma, clinical studies show the serum elimination half-life was an average of 26 days with clearance that averaged 2.4 ± 1.1 mL /kg/day. Body weight increases clearance. Specifically, double the body weight led to double the apparent clearance. For individuals with chronic hives, the serum elimination half-life was an average of 24 days with clearance that averaged 240 mL/day.

How long does it take for Xolair to get out of your system?

The body takes an average of 26 days to eliminate this drug from your system if you take it for asthma. If you take it for chronic hives, this average is 24 days. The amount of time for clearance depends on several factors, such as body mass.

Is omalizumab an immunosuppressant?

Omalizumab is an immunosuppressant, although it does not work the same way as more traditional types of immunosuppressants, such as cyclosporine, do. Omalizumab only affects the part of the immune system that handles allergies, so it does not raise the risk of illness or infection.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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