Xolair (omalizumab) is a brand-name drug that’s prescribed for allergic asthma, hives, and nasal polyps in adults and some children. Xolair comes as a subcutaneous injection that’s typically given every 2 or 4 weeks. The dosage can vary depending on what condition the drug is used to treat.
Xolair is approved by the Food and Drug Administration (FDA) to treat:
- long lasting moderate to severe allergic asthma
- chronic urticaria (hives) with no known cause
- nasal polyps in adults, when used in combination with other medications
Xolair is a biologic and belongs to a drug class called monoclonal antibodies. Xolair is not available in a biosimilar version.
Keep reading for specific information about the dosage of Xolair, including its strengths and how to use the medication. For a comprehensive look at Xolair, see this article.
Note: This article describes typical dosages for Xolair provided by the drug’s manufacturer. When using Xolair, always follow the dosage prescribed by your doctor.
Below is a Xolair dosing guide for its approved conditions. The Xolair adult and children’s dosages are described below. However, you should always take your dose as prescribed by your doctor.
The Xolair dosing frequency depends on the condition it’s being used to treat. For example, you may take Xolair more often to treat allergic asthma or nasal polyps than to treat urticaria (hives).
Xolair forms
Xolair comes as a solution given as a subcutaneous injection using a syringe or an autoinjector pen. Each syringe and autoinjector is prefilled with a single dose of medication.
Xolair also comes as powder in single-dose vials. Powder-filled vials are mixed with sterile water by your healthcare professional to form a solution for injection.
Xolair strengths
Xolair autoinjectors come in three strengths:
- 75 milligrams (mg) per 0.5 milliliter (mL)
- 150 mg/mL
- 300 mg/2 mL
Xolair prefilled syringes come in two strengths:
- 75 mg/mL
- 150 mg/mL
Xolair single-dose vials come in one strength: 150 mg. For this use, Xolair comes as a powder that’s mixed with sterile water to form a solution.
Typical dosages
The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.
Dosage for chronic hives
The typical dosage of Xolair to treat chronic (long-term) hives with an unknown cause is 150 mg or 300 mg once every 4 weeks. This is the recommended dose for people ages 12 years and older whose symptoms have not eased with certain other antihistamine drugs.
Dosage for allergic asthma
The typical dosage of Xolair is 75 mg to 375 mg once every 2 or 4 weeks to treat long lasting, moderate to severe asthma in people with both:
- allergic asthma with a positive skin or blood test to certain year-round allergens, and
- asthma symptoms that aren’t managed by inhaled corticosteroids
This is the recommended dosage range for people ages 6 years and older. Your dosage is based on your body weight and your level of immunoglobulin E (IgE), which is determined by a blood test that you’ll receive before you start treatment.
Below are Xolair dosing guides based on body weight and IgE level for people ages 12 years and older. However, you should always take the dosage prescribed by your doctor.
Xolair dosage when taken every 4 weeks:
| Body weight in kilograms (kg)* | ||||
| 30 kg to 60 kg | more than 60 kg to 70 kg | more than 70 kg to 90 kg | more than 90 kg to 150 kg | |
| Pretreatment IgE level in international units per milliliter (IU/mL) | Dose in mg | |||
| 30 to 100 | 150 | 150 | 150 | 300 |
| more than 100 to 200 | 300 | 300 | 300 | no recommended dose |
| more than 200 to 300 | 300 | no recommended dose | no recommended dose | no recommended dose |
Xolair dosage when taken every 2 weeks:
| Body weight in kg | ||||
| 30 kg to 60 kg | more than 60 kg to 70 kg | more than 70 kg to 90 kg | more than 90 kg to 150 kg | |
| Pretreatment IgE level in IU/mL | Dose in mg | |||
| more than 100 to 200 | no recommended dose | no recommended dose | no recommended dose | 225 |
| more than 200 to 300 | no recommended dose | 225 | 225 | 300 |
| more than 300 to 400 | 225 | 225 | 300 | no recommended dose |
| more than 400 to 500 | 300 | 300 | 375 | no recommended dose |
| more than 500 to 600 | 300 | 375 | no recommended dose | no recommended dose |
| more than 600 to 700 | 375 | no recommended dose | no recommended dose | no recommended dose |
* For reference, 1 kg is about 2.2 pounds (lb).
Dosage for nasal polyps
The typical dosage of Xolair to treat nasal polyps in adults when used in combination with other medications is 75 mg to 600 mg once every 2 or 4 weeks.
Your dosage is based on your body weight and your level of IgE, which is determined by a blood test you’ll receive before you start treatment. Your doctor will prescribe the dosage that’s right for you.
Talk with your doctor or visit the drug’s prescribing information to learn more about the dosages based on body weight and IgE level.
Children’s dosage
Xolair pediatric dosing depends on the condition it’s being used to treat. Xolair is approved for use in some children to treat allergic asthma and chronic hives.
Children’s dosage for allergic asthma
Xolair is approved to treat moderate to severe asthma in children ages 6 years and older with both:
- allergic asthma with a positive skin or blood test to certain year-round allergens, and
- asthma symptoms that aren’t managed by inhaled corticosteroids
The typical dosage for children ages 12 years and older is the same as it is in adults. See the “Dosage for allergic asthma” section just above for details.
For children ages 6 years to 11 years, the Xolair dosage is based on their body weight and their level of IgE. Their IgE level will be determined by a blood test they’ll receive before treatment is started.
Talk with your child’s doctor or visit the drug’s prescribing information to learn more about dosages based on body weight and IgE level.
Children’s dosage for chronic hives
To treat chronic hives with an unknown cause, the typical dosage for children ages 12 years and older is the same as it is in adults. See the “Dosage for allergic chronic hives” section just above for details.
Long-term treatment
Xolair is meant to be a long-term treatment. If you and your doctor determine that Xolair is safe and effective for you, you’ll likely take it long term.
Find some answers below to commonly asked questions about Xolair.
Is there a dosing chart for Xolair?
Yes, the drug’s manufacturer provides a dose chart with recommended dosages and dosing schedules for certain conditions that Xolair is used to treat.
The dosing charts provide recommended dosages based on body weight and immunoglobulin E (IgE) level when Xolair is used to treat:
- allergic asthma in people ages 12 years and older
- allergic asthma in children ages 6 years to 11 years
- nasal polyps in adults
Treatment of urticaria (hives) from an unknown cause is not based on body weight or IgE level. For this reason, a dosing chart is not available for this use.
If you have questions about your dose of Xolair, talk with your doctor. Also, see the “Dosage for allergic asthma” section above for a dosing chart for asthma in people ages 12 years and older.
Will my doctor use a dosing calculator to determine my dose of Xolair?
Your doctor will likely use a dosing table or chart to determine your dosage instead of a dosing calculator. This is because they’ll use both your body weight and your IgE level, which is measured by a blood test, to determine your dosage for allergic asthma or nasal polyps.
They’ll calculate your body weight in kilograms (kg)* and evaluate your blood test results to determine the dosage of Xolair that’s right for you.
For chronic hives from an unknown cause, there are specific recommended dosages. For this reason, your doctor won’t need to make dosage calculations. See the “Dosage for chronic hives” section above for more information.
If you have more questions about how your dose of Xolair will be determined, talk with your doctor or pharmacist.
* For reference, 1 kg is about 2.2 pounds (lb).
What is Xolair’s price per dose?
The price per dose of Xolair depends on your insurance coverage, your treatment plan, the cost of your visits to your doctor’s office, and the specialty pharmacy you use.
If you receive your doses of Xolair at your doctor’s office or clinic, talk with them about the price you’ll pay for your injections.
Talk with your insurance provider or specialty pharmacy to find out the exact cost you’ll pay per dose of Xolair if you self-administer your doses. Xolair is available only at specialty pharmacies that are authorized to carry specialty drugs.
If you have drug insurance coverage, you may be eligible for the Xolair co-pay program.
If you don’t have insurance coverage, you may be eligible to receive Xolair through the Genentech Patient Foundation program.
To learn more about Xolair’s cost, see this article.
The Xolair dosage your doctor prescribes will depend on several factors. These include:
- the type and severity of the condition Xolair is treating
- your weight
- your results from certain blood tests
- your age
Other medical conditions you have can also affect your Xolair dosage.
When you start Xolair treatment, you’ll receive a subcutaneous injection in a doctor’s office or clinic.
Your doctor will recommend how often you’ll need a dose depending on the condition Xolair is being used to treat. You’ll need to schedule your injection appointments to receive your doses.
Xolair can be injected into your abdomen or thighs. Your healthcare professional may inject it into the outer side of your upper arms.
In certain cases, you may be able to give yourself Xolair injections at home if your doctor recommends it. Xolair has a boxed warning about a risk of anaphylaxis (severe allergic reaction). They’ll evaluate your ability to identify and treat anaphylaxis right away before you start injecting Xolair yourself.
If self-injecting your doses is a good option for you, your doctor will show you how to inject Xolair prefilled syringes. There is also a step-by-step video and instructions for use on the drug manufacturer’s website showing how to inject Xolair.
To learn more about how Xolair is given, talk with your doctor.
ACCESSIBLE DRUG LABELS AND CONTAINERSSome pharmacies offer labels with large print, braille, or a code you scan with a smartphone to convert text to speech. If your specialty pharmacy doesn’t have these options, your doctor or pharmacist might be able to recommend a pharmacy that does.
Call your doctor’s office right away if you miss your appointment to receive your Xolair dose. They can help you schedule another appointment to receive your injection.
If you are injecting Xolair at home and miss a dose, call your doctor right away so that they can advise when you should take your next dose.
To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.
The dosages in this article are typical dosages provided by the drug’s manufacturer. If your doctor recommends Xolair for you, they will prescribe the dosage that’s right for you. Always follow the dosage that your doctor prescribes.
As with any drug, never change your dosage of Xolair without your doctor’s recommendation. If you have questions about the dosage of Xolair that’s best for you, talk with your doctor.
Besides learning about dosage, you may want other information about Xolair. These additional articles might be helpful:
- More about Xolair. For information about other aspects of Xolair, refer to this article.
- Side effects. To learn about side effects of Xolair, see this article. You can also look at the Xolair prescribing information.
- Drug comparison. Find out how Xolair compares with Dupixent and Nucala.
- Cost. If you’d like to learn about Xolair and cost, see this article.
- Details about your condition. For details about your condition, see our asthma and allergies hub.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.
