A food allergy is the body's abnormal response to a food. The immune system releases histamine and other chemicals causing a reaction, which can occur in several organ systems. Limbic system - mood swings, headaches, fatigue.
Allergic reactions can occur within minutes, or up to hours, or even days after eating food.
In the most severe form, Anaphylaxis, patients may have symptoms in all these organ systems, a drop in blood pressure, unconsciousness, and in some cases die. Extra care should be taken if a child has asthma and food allergies. It is important to learn the scientific and technical names for foods in ingredient lists and always read all food labels in order to avoid problem foods.