ALEX3 Allergy Test – 300 Allergens

Measures Total IgE and allergen-specific IgE across the ALEX3 panel of 300 allergens. The results can show patterns of sensitisation to foods and environmental sources, but sensitisation is not the same as a clinical allergy and must be interpreted alongside symptoms and exposure history.

At a glance

• Sample: Capillary blood in a Gold Microtainer (400–600 µL)
• Collection: Collect the blood sample at home using TDL self-collect kit KT353
• Estimated turnaround: 3–4 days from laboratory receipt of a usable sample

What this test measures

Total IgE

The overall amount of immunoglobulin E in blood. It can provide context for an allergic tendency but does not identify a specific trigger on its own. An in-range or out-of-range result is not a diagnosis by itself; clinicians interpret it using the laboratory range, symptoms, medical history and related tests.

ALEX3 allergen panel

Specific IgE sensitisation across 300 allergens from sources including animal dander, cereals, egg, legumes, milk, mites, moulds, pollen, seafood, tree nuts and venoms. An in-range or out-of-range result is not a diagnosis by itself; clinicians interpret it using the laboratory range, symptoms, medical history and related tests.

Molecular allergens

The panel includes 218 allergen molecules, 107 of which TDL describes as unique to ALEX3. Component-level results may help a clinician distinguish genuine sensitisation from cross-reactivity. An in-range or out-of-range result is not a diagnosis by itself; clinicians interpret it using the laboratory range, symptoms, medical history and related tests.

How clinicians use this test

Clinicians use Total IgE, ALEX3 allergen panel and Molecular allergens to look for IgE sensitisation and then compare the result with the person’s exposure and reaction history. Sensitisation is not the same as clinical allergy, and the test cannot predict reaction severity.

Is this the right test for you?

Someone exploring a suspected allergy with a clinician who can interpret the laboratory result alongside a detailed reaction history.

Preparation and collection

Return the sample on the same day it is collected. Do not post over weekends or bank holidays.

Understanding your result

The report shows which of the listed allergen markers produced measurable IgE and may grade the response. A higher laboratory class does not reliably predict how severe a real-life reaction will be, while a negative result cannot rule out every allergy mechanism.

Your results and next steps

Compare any sensitisation result with what happens during real exposure. Do not start broad avoidance from the laboratory value alone; discuss significant reactions with an allergy clinician and a dietitian when food exclusion is being considered.

Limitations

A laboratory antibody result must be interpreted with exposure and reaction history. Sensitisation is not the same as clinical allergy and a result cannot predict reaction severity.

When to get medical help

Sudden breathing difficulty or swelling of the mouth, tongue or throat may be anaphylaxis: call 999 immediately.