Most cases of food allergies occur when someone with a genetic predisposition produces specific IgE antibodies to the certain protein of a particular food. When these IgE antibodies react to a specific protein, the release of chemicals from cells is triggered.
Allergic symptoms include hives, swelling of the lips and tongue, trouble breathing, a drop in blood pressure and even loss of consciousness. They can appear from within minutes to several hours after a person has eaten the food to which he or she is allergic.
Although all foods can cause an allergy, peanuts, tree nuts, fish, shellfish, eggs, soy, milk and wheat account for 90 percent of all food allergies. Peanut and tree nut allergies affect about 1 percent of the population. Peanuts are the leading cause of severe allergic reactions, followed by shellfish, fish, tree nut and eggs.
Studies have shown that one-third of people with a peanut allergy have experienced a severe allergic reaction. The first allergic reaction to peanut or tree nut develops in most children between 14 and 24 months of age. The peanut or tree nut allergy was once considered lifelong, yet new research has determined that up to 15 to 20 percent of sufferers will actually outgrow the allergy by school age. This is especially true if your child has few other food allergies, has a low peanut IgE level as shown on a blood test, or has a mild reaction to skin prick test at a time of reassessment.
The peanut is in the legume family, along with peas, lima beans, lentils and soybeans, just to list a few. If you are allergic to peanuts, it does not necessarily follow that you will be allergic to these other legumes and be required to avoid them also. Tree nuts include almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachio nuts and walnuts. Although the peanut is not considered a tree nut, it is recommended that peanut-allergic patients avoid all tree nuts, and vice versa, as an extra precaution.
Allergy shots have not been successful for patients with peanut or tree nut allergy. Until a cure is found, the only “cure” for the peanut or tree nut allergy is to stay away from all peanut and tree nut products. Read labels of every food that you eat. Peanuts and peanut products can show up in many unsuspecting foods. In highly sensitized people, even trace amounts can induce a severe allergic reaction.
The principal treatment of acute severe allergic reaction is epinephrine. People with peanut or tree nut allergy should carry self-injection devices such as EpiPen with them at all times. After epinephrine is administered, they should be observed for the next four to eight hours at a medical facility and receive additional treatment, if necessary.
Non-generalized allergic reactions are treated with a high dose antihistamine, while anaphylaxis requires immediate medical treatment with epinephrine and possible corticosteroids, in addition to the antihistamines. Unfortunately, strict avoidance of the allergy-causing food is the only way to avoid a reaction.