Skin testing is the most reliable form of allergy testing. Because mast cells are located in high numbers just under the skin, results of skin testing have proven to be more accurate than blood testing in diagnosing allergies.
The allergy testing procedure
Skin testing is a simple series of tiny scratches made on your back. Staff uses a small instrument similar to a plastic toothpick, which contains trace amounts of a single allergen, such as mold, pollen, dust mite, and pet dander to perform the allergy test. When the results are positive, a small reaction on the skin occurs, usually within 20 minutes. This reaction is generally a small bump, similar to a mosquito bite, and may cause some itchiness. A bump or reaction indicates that you are allergic to that specific trigger. Following the scratch test on the back, some patients may also receive intradermal testing, where a small amount of the allergen is injected under the skin of the arm to see if it causes a reaction.
What age is appropriate for allergy skin testing?
Per the American Academy of Pediatrics, age is not a barrier to skin testing. Even infants can benefit. As the child’s immune system develops, the child should be retested to identify changes in his/her immune response. Many times foods can be reintroduced into the diet that once caused an allergic reaction. In addition to Allergy & Immunology, our allergists train in either pediatrics or internal medicine, so we are very comfortable treating pediatric patients for allergies and asthma.
Are you really allergic to certain foods?
Food allergy is when the body mistakes a certain food as “dangerous” and produces an antibody called immunoglobulin E (IgE). This IgE antibody reacts with the allergen (i.e., dangerous food item) and chemicals are released into the body causing an allergic reaction. Symptoms of a food allergy reaction may be mild (rashes, hives, itching, swelling) or severe (trouble breathing, wheezing, loss of consciousness). A food allergy can potentially be fatal.
Avoidance is the only treatment for food allergy. There is no cure. Neither desensitization nor shots have proven to be a safe or an effective way of reducing food allergy reactions.
Food Allergy vs. Adverse Food Reaction
Food allergies are often confused with adverse food reactions. Lactose intolerance is an example of an adverse food reaction. A person who is lactose intolerant lacks the proper enzymes to digest the sugar found in milk and dairy products properly. This affects the digestive system and a person may have symptoms of diarrhea and stomach cramping if he/she ingests a milk or dairy product. The severity of symptoms is generally related to the amount of food ingested.
A food allergy, on the other hand, involves the immune system. While the symptoms of a minor food allergy and adverse food reactions may be similar, the biology is different. The release of chemicals in an allergy attack can cause symptoms as minor as a scratchy throat, sniffles, and puffy eyes to major symptoms like swelling of the tongue and throat, coughing, and/or hives covering the entire body. In rare instances, if someone has a food allergy, ingestion of that food can lead to anaphylaxis, a severe allergic reaction that can be fatal.
Less than 5 percent of the population has a true food allergy. This small number, though, and should not minimize the importance of recognizing and treating a food allergy.
Information from: https://www.familyallergy.com/education/allergy/food/