What does this test include?
ALEX is a broad blood panel that measures total IgE and specific IgE to allergen extracts and molecular components from foods, pollens, mites, animals, insects and molds.
Why might it be ordered?
- For complex sensitization to multiple allergens, when a detailed sensitization profile may help the allergist.
- To distinguish primary sensitization from some cross-reactions and for specialized planning of next steps.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
Fasting is usually not required. Describe your symptoms, the possible exposures and how soon each reaction began. Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How are the results reported?
The report shows patterns of IgE sensitization to many extracts and components. Each result is associated with the clinical history; not all positive components cause symptoms. Detectable specific IgE indicates sensitization, not necessarily clinical allergy. The results should match actual post-exposure symptoms.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.