What is the Difference Between IgG and IgE?

IgG and IgE are two types of immunoglobulins, or antibodies, that play different roles in the immune system. The main differences between them are:

1. Immune Response: IgE antibodies are involved in a rapid immune response, while IgG antibodies are involved in a more delayed immune response.
2. Allergic Reactions: Both IgG and IgE antibodies indicate an allergic reaction, but there are key differences between the two types of reactions. IgE-mediated reactions are considered true food allergies and are characterized by immediate hypersensitivity reactions, such as hives, swelling, or anaphylaxis. In contrast, IgG-mediated reactions are associated with food sensitivities and are usually delayed, taking hours to days to appear.
3. Symptoms: IgE reactions result in symptoms that are more immediate and severe, such as skin rashes, swelling, wheezing, or anaphylaxis. On the other hand, IgG reactions are associated with food intolerance and can cause symptoms like digestive upset, headaches, fatigue, brain fog, joint pain, or skin itching and rashes.
4. Testing: IgE allergic reactions can be tested using skin prick or patch testing, as well as blood testing. Testing for IgG and IgA-mediated reactions typically involves measuring antibody levels in the blood.

In summary, IgG and IgE antibodies play different roles in the immune system, with IgE being associated with immediate hypersensitivity reactions (true food allergies) and IgG being associated with delayed immune responses (food sensitivities). Both types of reactions can be tested for, but the methods and implications for diagnosis and management may differ.

Comparative Table: IgG vs IgE

IgG and IgE are two classes of immunoglobulins (antibodies) that play different roles in the immune system. Here is a table highlighting the differences between them:

In summary, IgG is mainly involved in fighting viral and bacterial infections, while IgE is associated with allergies and parasitic infections. IgG plays a crucial role in the biological defense system, and it is the only immunoglobulin that can pass through the placenta to protect a newborn.