A peanut allergy is a type of food allergies or a reaction that occurs when body wrongly identifies peanuts as harmful substances to the body system. When peanuts are eaten or food containing peanuts has been eaten, the body’s natural defense system which is the immune system, that fights infections and diseases-overreacts and can cause a serious, even life-threatening response. The most severe allergies, in general, can result in anaphylaxis, an emergency situation requiring immediate attention and treatment with epinephrine. It is usually treated with an exclusion diet and vigilant avoidance of foods that may contain whole peanuts or peanut particles and/or oils.
What Causes a Peanut Allergy?
An allergic reaction occurs when your immune system overreacts and releases chemicals, including histamine, into your blood. These chemicals can affect different tissues in the body, such as the skin, eyes, nose, airways, intestinal tract, lungs, and blood vessels. It’s not clear why peanuts trigger this response in some people.
Symptoms of Peanut Allergy
Symptoms of peanut allergy are related to the action of Immunoglobulin E (IgE) and other anaphylatoxins, which act to release histamine and other mediator substances from mast cells (degranulation). In addition to other effects, histamine induces vasodilation of arterioles and constriction of bronchioles in the lungs, also known as bronchospasm (constriction of the airways).
Symptoms can include the following: Symptoms of peanut allergy can range from mild to life-threatening. If you have a mild reaction, you may get a stomach ache, a runny nose, an itchy skin rash, hives, or tingling in your lips or tongue. If your reaction is worse, you may develop additional symptoms such as a tight throat, hoarse voice, wheezing, coughing, feeling sick to your stomach, vomiting, belly pain, and diarrhea. Your symptoms may start from within a few minutes to a few hours after eating peanuts or peanut products.
People who are allergic to peanuts may have a life-threatening reaction called anaphylaxis. Symptoms of anaphylaxis can include problems breathing and swallowing, vomiting and diarrhea, dizziness, dangerously low blood pressure, swelling of the lips, tongue, throat, and other parts of the body, and loss of consciousness. If not treated, death can result. Anaphylaxis usually occurs within minutes but can occur up to several hours after eating peanuts or peanut products.
Diagnoses of Peanut Allergy
To diagnose a peanut allergy, your doctor will start with a medical history and a physical exam. Your doctor will ask about any family food allergies, especially siblings with peanut allergies. He or she will ask detailed questions about your symptoms, how soon your symptoms began after you ate the food, and if any over-the-counter allergy medicines like an antihistamine were helpful. Your doctor will ask if other people also got sick, how the food was prepared, and what other foods were eaten.