What Happens In An Allergic Reaction

An allergic reaction is triggered when the immune system mistakenly overreacts to a food that it thinks is a harmful invader. This overreaction causes symptoms that may appear within seconds to hours after eating a trigger food.

Food allergies differ from food intolerances. A food allergy occurs when the immune system reacts to a food protein causing symptoms that can affect the respiratory system, gastrointestinal tract, skin, and/or cardiovascular system. An intolerance is a metabolic disorder and does not involve the immune system.

Fortunately, most allergic reactions are mild. They may cause a runny nose, sneezing, itching skin, hives, and digestive upset. For those who are severely allergic, exposure to a trigger food may cause life-threatening reactions. The tongue, lips, or throat may swell so severely that the person cannot breath. Death will occur without immediate medical help. Unfortunately, sudden severe allergic reactions (known as anaphylaxis) to food cause 200 deaths annually in the United States. Those that suspect they have a food allergy should seek medical advice promptly.

The prescription drug epinephrine, also called adrenaline, is used to control severe reactions and must be carried at all times by those at risk. An antihistamine should also be administered. Call 911 in cases of severe food allergy reactions, even if epinephrine has been administered and the reaction seems to be under control.

Strict avoidance of the allergy-causing food is the only way to prevent a reaction. Reading ingredient labels of all foods to be consumed and knowing alternative names for allergens (such as whey and casein for milk) as well as preventing cross-contact of utensils and hands are the keys to controlling food allergies.