Allergic Reactions

Whenever we fill out medical forms, it is common to see a question asking if we have any allergies. Allergies can range in severity, as not everyone has the exact same response to a particular substance. No matter so, they are still important to be aware of. Even if you lack such a condition, it is probable that you know someone who has them. Common allergies include pollen, animal dander, nuts, eggs, fish, penicillin, and the list goes on. In fact, ninety percent of food allergies are composed of these eight foods-- milk, eggs, peanuts, tree nuts, soy, wheat, fish, and shellfish. Since these are foods that may be rather common in our diets, they are definitely worth paying attention to.

Before looking into the symptoms of allergies, it is worth noting that being allergic and being intolerant to foods are quite different. While they share similar symptoms such as stomach pain, vomiting, diarrhea, and nausea, allergies are generally more serious and may be life-threatening, while intolerance is not. In addition, food intolerance may occur only if the food is consumed in a large amount or is constantly being consumed. The major factor differentiating the two comes down to the reason why allergic reactions occur. Allergies take place when one’s immune system recognizes these allergens as harmful and foreign, causing what we refer to as an allergic reaction in attempts to fight against this substance. On the other hand, intolerance refers to a food that causes irritation to the stomach or increases difficulty in digesting it. A typical example is lactose intolerance, which is when a person is lacking the lactase enzyme that facilitates the breakdown of lactose.

The symptoms for allergic reactions are on a spectrum, ranging from mild to severe. Mild symptoms include hives, a rash, being itchy, nasal congestion, a scratchy throat and watery eyes. More severe symptoms include abdominal cramping and pain, diarrhea, difficulty swallowing or breathing, nausesa, tightness in the chest, and swelling of the face, eyes, and tongue. Most severe of all is anaphylaxis, in which the symptoms include a rash, low pulse, and shock. To combat anaphylactic shock, epinephrine is a commonly used solution to minimize the reaction. In the worse case, blood pressure will immediately drop and airways will narrow, leading to fatal complications and potentially death. Allergies can cause a wide range of effects on the human body, and therefore for those with allergies, it is important to note how extreme reactions can potentially be. This is particularly crucial as allergic reactions can become more severe over time, especially if there is increased contact with the allergen.

There are three methods that can be used to diagnose allergies-- skin tests, challenge (elimination) tests, and blood tests. Skin tests involve applying a small amount of the suspected allergen on the skin, and observing that area. The allergen can be applied as a patch test (taped to skin), skin prick test (pricked into skin), or intradermal test (injected under the skin). Skin tests are mainly used for diagnosing allergies to foods, pollen, penicillin, and venom. Challenge tests are more limited in that they are used to diagnose food allergies, since it requires one to remove the suspected food from one’s diet for a few weeks. After this test period, one should consume the food again and see if there are any changes. Lastly, blood tests are used to check if there are antibodies in the blood that are against a certain allergen. Blood testing is used when a skin test has proved to not be helpful or is not possible.

While we can not completely get rid of our allergies, there are over-the-counter medications available for those with mild reactions, such as Benadryl, Allegra, and Claritin. For those with more severe reactions, it would be best to avoid these allergens, and if necessary, carry an EpiPen. Consultation with a doctor may be necessary if the reactions are severe and life-threatening. Allergies are one of the most prevalent conditions in society and therefore, it does not hurt to understand them better, especially if you or a loved one has one.


Stephanie Chan