Serum immunoglobulin E (IgE) is a type of antibody found in the blood. It plays a key role in allergic reactions and immune responses to parasites. IgE levels are often elevated in individuals with allergies, asthma, or parasitic infections.

Measuring IgE levels in the blood can help diagnose allergic conditions and monitor the effectiveness of allergy treatments. Elevated levels may indicate an allergic response to specific allergens, such as pollen, dust mites, pet dander, or certain foods. However, it’s essential to interpret IgE levels in the context of a person’s symptoms and medical history, as elevated levels alone do not necessarily confirm an allergy.