Immunoassay for Immunoglobulin E (IgE) Substance Concentration in Serum or Plasma

Why This Test Is Done

Doctors may order an IgE test to diagnose allergies, assess severe allergic reactions (such as anaphylaxis), evaluate immune system responses, or monitor conditions like asthma or chronic urticaria. It can also help determine if a patient is at risk for certain allergic diseases or reactions to medications.

What to Expect Before the Test

No special preparation is usually needed. You may have a small needle inserted into a vein (venipuncture) in your arm to draw blood. If a urine sample is involved, you might be asked to collect a sample at home or in a lab setting. Always follow your healthcare provider’s instructions.

What the Test Results Mean

Results are interpreted by your healthcare provider based on your medical history and symptoms. Elevated IgE levels often indicate allergies or immune system sensitivities, while very high levels may suggest conditions like atopic dermatitis or certain parasitic infections. Normal or low levels do not definitively rule out allergies but may help narrow down further testing.

Common Conditions Monitored or Diagnosed

IgE testing is commonly used to diagnose allergies (e.g., to foods, pollen, pet dander), allergic rhinitis, asthma, eczema, and other allergic conditions. It may also help guide treatment plans, such as allergy immunotherapy (allergy shots).