Types of Immunoglobulins

• The mucous membranes contain high amounts of immunoglobulin A (IgA), which often increases during an allergic reaction. Because all bodily fluids contain immunoglobulin G (IgG), it is the most easily detected immunoglobulin. Immunoglobulin M (IgM), present mostly in blood and fluid from the lymph nodes, is always the first immunoglobulin produced when the body detects an allergen or infection. Immunoglobulin E (IgE), also linked to allergic reactions, mainly develops in the skin, mucous membranes and lungs. Immunoglobulin D (IgD), can barely be detected in blood, and is therefore the one that doctors least understand.