Description

The IgE test measures the amount of immunoglobulin E antibodies in your blood. IgE is part of your immune system and plays a major role in allergic reactions.

When you’re exposed to an allergen—such as pollen, dust mites, pet dander, certain foods, or insect venom—your immune system may produce IgE antibodies as part of its defense. This can trigger symptoms such as:

  • Sneezing or runny nose
  • Itchy or watery eyes
  • Hives or rash
  • Swelling
  • Breathing difficulties

A high IgE level suggests your body may be overreacting to an allergen, which can help guide allergy diagnosis and management.

IgE Qualification in Biologic Treatment

In some cases—particularly for severe allergic asthma—your IgE level is measured to see if you qualify for treatment with certain biologic medications, such as omalizumab. These drugs specifically target IgE to reduce allergic inflammation. To be eligible, a patient must typically have elevated IgE levels along with specific clinical symptoms.

Fasting: Not required.