All About Xolair Injection Site Reaction

You may experience a side effect known as an injection site reaction following a Xolair (omalizumab) injection. An injection site reaction is characterized by swelling, redness or soreness that occurs in the area where your doctor or nurse gave you the Xolair injection.

A nurse giving a patient an injection in the hospital

Jose Luis Pelaez Inc. / Getty Images

Additional symptoms of an injection site reaction include:

  • Bruising
  • Burning
  • Hive formation
  • Inflammation
  • Itching
  • Pain
  • Stinging

The injection site reaction most commonly occurs within an hour of the Xolair injection, but may occur up to a day or so later. Additionally, an injection site reaction is less likely to occur with each subsequent Xolair injection. Finally, an injection site reaction following your Xolair injection is usually not serious and can be handled with simple, local treatments, such as:

  • Placing a cold compress over the red swollen area.
  • Taking over-the-counter medications, such as antihistamines to decrease itching, and analgesic medications to reduce pain and swelling.

Before leaving your doctor's office, make sure you know how to care for your injection site and what to do for expected problems.

Preventing an Injection Site Reaction

An injection site reaction following a Xolair injection occurred in 45% of patients involved in clinical trials. Consider these measures that may help prevent an injection site reaction:

  • Make sure the person giving you the shot washes their hands and uses an alcohol swab to clean your skin before giving you the Xolair injection. If they do not, you should ask them to do so before getting the shot.
  • Ask your asthma care provider to rotate the part of your body where you receive the Xolair injection.
  • Do not rub the Xolair injection site after getting your shot.
  • Wear loose-fitting clothing to your appointment, as the fabric can irritate the Xolair injection site.
  • Ask your doctor's office if they are prepared to treat an anaphylactic reaction.
  • Make sure to discuss with your doctor whether you need to be prescribed an epinephrine injector.
  • If you need an epinephrine injector, make sure you know how to correctly use it.
  • Consider a Medic-Alert bracelet in case you develop a reaction, are unable to administer the epinephrine injector, and are unable to talk with emergency responders.

Many doctor's offices will require you to be monitored after your injection. A common scenario is that you will need to stay in the doctor’s office for 2 hours after the first several shots are given—commonly 3 to 5 injections. If you do not experience any reactions after this first group of injections, you will need to stay in the doctor's office for 1 hour after the shot is given.

What Should My Doctor's Office Be Doing?

You will receive your Xolair injection every 4 weeks. It needs to be kept under specific refrigeration conditions at your doctor's office before being prepared for your injection. The injection is slightly viscous and will take longer, usually 10 to 15 seconds, to administer.

Your doctor's office will draw the Xolair medication into a syringe along with saline to prepare the injection. Each time a needle is used the area, whether your skin or a vial, must be clean with an alcohol pad. The nurse will then administer the injection subcutaneously over 10 to 15 seconds.

When to Call Your Doctor

If pain, swelling, and redness continue, or if you are concerned that there may be an infection, you should call your doctor immediately. If you experience any symptoms of anaphylaxis, go to the nearest emergency room.

Anaphylaxis usually occurs in the first two hours after an injection. While it is more common to occur after the first injection, it can occur after any subsequent injection. Hives or tongue swelling are other symptoms that require immediate treatment. If you have an epinephrine injector it should be given and you should seek emergency care. If you do not have an epinephrine injector, you should immediately seek emergency care.

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  • FDA Post-market Drug Safety Information for Patients and Providers. Omalizumab (marketed as Xolair). Prescribing information