A quick bit on some information about food allergies...
Food allergies are when the body reacts to the protein in a certain food as if it is harmful to the body. An immune system reaction happens where the body tries to fight off the food because it recognizes it as bad. Symptoms can include itchy, watery eyes, runny nose, itching, tingling or burning tongue, difficulty swallowing, difficulty breathing, stomach pain, nausea, vomiting, diarrhea. The most severe reaction is called anaphylactic shock where multiple reactions happen which could lead to low blood pressure, and death.
The most common allergens, the BIG 8, are peanuts, tree nuts, shellfish, milk, egg, fish, soy, and wheat. Children are more likely to outgrow some of these than others. For example, children are more likely to outgrow their egg allergies, but it is unlikely children outgrow peanut and shellfish allergies.
There is no cure and no pill for food allergies. The treatment is avoidance and often times strict avoidance of certain foods depending on the severity of the allergic reaction. There is a nice weapon for those with food allergies though called the EpiPen. It is intended for use by people with food allergies after they have eaten a food they are allergic to. It helps the body stop reacting to, or to at least slow the reaction, to a food allergen until they can get to the hospital.
This is the very brief run down on food allergies.
Please post questions, comments, things I didn't address!