Most people are allergic to eggs, peanuts, milk, shellfish, wheat, and soy. Precautions you can take is to not cross contaminate, and not eat any foods your allergic to and always carry and Epi pen. Symptoms of a food allergy may be throwing up, hives, rashes, digestive problems, throat closing up, tingling lips, nausea, diarrhea, indigestion. A food allergy can last anywhere from a few minutes to two days long.