Research has not determined why peanuts trigger allergic reactions in children, but exposure to peanuts creates an overreaction of the immune system that causes an allergic reaction by releasing chemicals such as histamine into the blood, explains WebMD. The chemicals cause reactions to occur in the blood vessels, intestinal tract, lungs and airways. Some people also experience reactions in the skin, eyes and nose.
The body identifies peanuts as harmful substances during an allergic reaction, which can cause life-threatening and serious responses, according to WebMD. Children who experience an allergic reaction from peanuts should seek immediate medical attention.
Mild reactions to peanuts may cause tingling of the tongue or lips, hives, itchy eyes, a runny nose, or a stomachache in children, explains WebMD. More severe reactions may cause children to wheeze, cough, develop a tight throat or hoarse voice, and feel sick to their stomach. Symptoms may occur immediately or after a few hours after exposure to peanut products. Severe symptoms include vomiting, diarrhea, dizziness, lowered blood pressure and swelling of parts of the body such as the tongue, throat or lips. Life-threatening reactions can cause anaphylaxis and a loss of consciousness.
Physicians diagnose peanut allergies by conducting a physical exam and an evaluation of symptoms and reviewing family food allergies, according to WebMD.