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Omalizumab Injection

Omalizumab Injection 

En Español (Spanish Version)

(oh mah lye zoo' mab)


Omalizumab injection may cause serious or life-threatening allergic reactions. You may experience an allergic reaction immediately after receiving a dose of omalizumab injection or up to 4 days later. Also, an allergic reaction can occur after you receive the first dose of medication or at any time during your treatment with omalizumab. Tell your doctor if you are allergic to omalizumab injection, and if you have or have ever had food or seasonal allergies, a serious or life-threatening allergic reaction to any medication, or sudden breathing problems.

You will receive each injection of omalizumab in a doctor's office or medical facility. You will stay in the office for some time after you receive the medication so your doctor can watch you closely for any signs of an allergic reaction. Tell your doctor if you experience any of the following symptoms: wheezing or difficulty breathing, shortness of breath, cough, chest tightness, dizziness, fainting, fast or weak heartbeat, anxiety, feeling that something bad is about to happen, flushing, itching, hives, feeling warm, swelling of the throat or tongue, throat tightness, hoarse voice, or difficulty swallowing. Call your doctor immediately or get immediate emergency medical attention if you experience any of these symptoms after you leave your doctor's office or medical facility.

Your doctor will give you the manufacturer's patient information sheet (Medication Guide) each time you receive an injection of omalizumab. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website ( or the manufacturer's website to obtain the Medication Guide.

Talk to your doctor about the risks of receiving omalizumab injection.

WHY is this medicine prescribed?

Omalizumab injection is used to decrease the number of asthma attacks (sudden episodes of wheezing, shortness of breath, and trouble breathing) in people with allergic asthma (asthma caused by inhaling substances such as dander, pollen, and dust mites) whose symptoms are not controlled with inhaled steroids. Omalizumab is also used to treat chronic hives without a known cause that cannot successfully be treated with antihistamine medications such as diphenhydramine (Benadryl), cetirizine (Zyrtec), hydroxyzine (Vistaril), and loratadine (Claritin). Omalizumab is not used to treat other forms of hives or allergic conditions. Omalizumab injection is in a class of medications called monoclonal antibodies. It works by blocking the action of a certain natural substance in the body that causes the symptoms of allergic asthma and hives.

HOW should this medicine be used?

Omalizumab injection comes as a powder to be mixed with water and injected subcutaneously (under the skin). When omalizumab is used to treat allergic asthma, it is usually injected once every 2 or 4 weeks. You may receive one or more injections at each visit, depending on your weight and medical condition. When omalizumab is used to treat chronic hives, it is usually given once every 4 weeks. Your doctor will determine the length of your treatment based on your condition and how well you respond to the medication.

It may take some time before you feel the full benefit of omalizumab injection. Do not decrease your dose of any other asthma or hives medication or stop taking any other medication that has been prescribed by your doctor unless your doctor tells you to do so. Your doctor may want to decrease the doses of your other medications gradually.

Omalizumab injection is not used to treat a sudden attack of asthma symptoms. Your doctor will prescribe a short-acting inhaler to use during attacks. Talk to your doctor about how to treat symptoms of a sudden asthma attack. If your asthma symptoms get worse or if you have asthma attacks more often, be sure to talk to your doctor.

Are there OTHER USES for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before receiving omalizumab injection,

  • tell your doctor and pharmacist if you are allergic to any medications or any of the ingredients in omalizumab injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: allergy shots (a series of injections given regularly to prevent the body from developing allergic reactions to specific substances) and medications that suppress your immune system. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had cancer.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using omalizumab injection, call your doctor.
  • talk to your doctor about whether there is a risk that you will develop a hookworm, roundworm, whipworm, or threadworm infection (infection with worms that live inside the body). Tell your doctor if you have or have ever had any type infection caused by worms. If you are at high risk of developing this type of infection, using omalizumab injection may increase the chance that you will actually become infected. Your doctor will monitor you carefully during and after your treatment.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do IF I FORGET to take a dose?

If you miss an appointment to receive omalizumab injection, call your doctor as soon as possible.

What SIDE EFFECTS can this medicine cause?

Omalizumab injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • pain, redness, swelling, warmth, burning, bruising, hardness, or itching in the place omalizumab was injected
  • pain, especially in the joints, arms, or legs
  • tiredness
  • ear pain
  • headache

• nausea

  • swelling inside of the nose, throat, or sinuses

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section or the SPECIAL PRECAUTIONS section, call your doctor immediately or get emergency medical treatment:

  • fever, muscle aches, rash, and swollen glands within 1 to 5 days after receiving a dose of omalizumab injection
  • shortness of breath
  • coughing up blood
  • skin sores
  • severe pain, numbness and tingling in your hands and feet

Some people who received omalizumab injection have had chest pain, heart attacks, blood clots in the lungs or legs, temporary symptoms of weakness on one side of the body, slurred speech, and changes in vision. There is not enough information to determine whether these symptoms are caused by omalizumab injection.

Omalizumab injection may increase the risk of developing certain types of cancer. There is not enough information to determine whether these cancers are caused by omalizumab injection.

Talk to your doctor about the risks of using this medication.

Omalizumab injection may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at ] or by phone [1-800-332-1088].

What should I do in case of OVERDOSE?

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to omalizumab injection.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving omalizumab injection or if you have received omalizumab injection within the past year.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand Names

  • Xolair®

Medication Information

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