If you suffer from persistent sniffing, sneezing, itching, or asthma, this test is the key to finding the cause. The Total IgE test measures the level of Immunoglobulin E, your body's "allergy antibody." High levels of IgE are a strong, direct indicator of an allergic process or sensitivity to allergens in your environment. This test is the foundational, first-line investigation for all allergic conditions, from hay fever to eczema. A simple blood draw provides the clear, quantitative answer you need to stop guessing and start building a treatment plan.