Xolair side effects: Risk of anaphylaxis highlighted in new black box warning

Austin Kirk

By Austin Kirk
Posted July 3, 2007


Yesterday the FDA released a new black box warning for the asthma drug Xolair (omalizumab), which will provide a stronger label regarding the risk of anaphylaxis, a serious and potentially fatal allergic reaction.  They also announced that  a new Medication Guide will be provided to those receiving the drug to provide information regarding the risk which could occur up to 24 hours or more after the medication is given. 

Xolair is a subcutaneous injection which was approved in 2003 for treatment of moderate to severe persistent asthma in adults and children over 11 years old.  The FDA requested that the manufacturer, Genentech, Inc., revise the warning label on February 21, 2007.  On July 2, 2007, the FDA released the updated WARNINGS, PRECAUTIONS and ADVERSE REACTIONS sections of the label together with the MEDICATION GUIDE, which was developed to be provided to patients when a prescription is filled or refilled.

>>FDA LINK: Xolair reaction guide for patients

Anaphylaxis is a severe allergic reaction which can be life-threatening.  While it usually occurs within two hours of receiving the medication, the Xolair reaction could occur after 24 hours or more.  The danger is seen at all dose levels and it could occur on the first dose, or it could occur even if the patient has not had a reaction previously when they received the drug.


Percentage of reported cases of Anaphylaxis which occur…

Within 30 minutes – 35%
Between 30 and 60 minutes – 16%
Between 60 and 120 minutes- 8%
Between 2 and 6 hours – 5%
Between 6 to 12 hours – 14%
Between 12 and 24 hours – 8%
Over 24 hours (up to 4 days) – 5%

Percentage of reported cases of anaphylaxis which occur after the…

First dose – 39%
Second dose – 19%
Third dose – 10%
Four or more doses – 32%

The FDA indicates that Xolair should only be administered at a healthcare center, and staff should observe patients for at least two hours, prepared to manage life-threatening anaphylaxis if it occurs.  It is also important for those who receive the injection to be aware of the risk of an Xolair reaction, and know the signs and symptoms.

Symptoms of anaphylaxis could involve:

  • Trouble breathing
  • Shortness of breath
  • Wheezing
  • Chest tightness
  • Low blood pressure
  • Dizziness
  • Fainting
  • Anxiety or feeling of “impending doom”
  • Itching
  • Hives
  • Swelling of the mouth
  • Throat tightness
  • Trouble swallowing

Since Xolair was approved in 2003, approximately 40,000 individuals in the United States have received the drug.  The Xolair side effects appears to cause anaphylaxis in about one of every 1,000 patients treated with the asthma drug.


The lawyers at Saiontz & Kirk, P.A. are reviewing potential Xolair lawsuits for any individuals who suffered permanent injuries from anaphylaxis as a side effect of the asthma drug.  If you, a friend or family member had a serious reaction from Xolair, requst a free claim evaluation.

No Comments • Add Your Comments

Add Your Comments

  • Have Your Comments Reviewed by a Lawyer

    Provide contact information below and additional private comments if you want an attorney to contact you to review a potential case.

    The information below will not be published to this page.

  • NOTE: Providing information for review by an attorney does not form an attorney-client relationship.

  • This field is for validation purposes and should be left unchanged.