Hives involve swelling, redness and itching. Allergies to certain foods, such as fish, eggs, milk, nuts and wheat induce intestinal disturbances and occur in children who usually outgrow it after age three. Anaphylactic shock is the most severe of all allergic reactions. Vomiting, cramps, and a sudden drop in blood pressure can also result. Anaphylaxis often occurs in persons particularly sensitive to penicillin, stinging insects and shellfish or nuts.
Many people have difficulty differentiating between a cold and an allergic attack.
Both are characterized by a runny or stuffed nose, sneezing and other symptoms. However, colds can include fever and aches and pains. An allergic attack begins almost immediately after exposure to allergens while a cold usually takes a few days to hit full force. Allergy symptoms last as long as you are exposed to the allergen, until the reaction ends. A cold should clear up within a few days to a week.