Allergies happen when the immune system begins to fight substances that are actually quite harmless to the body e.g. pollen or food. Common symptoms of an allergic reaction include watery eyes, sneezing attacks, an itchy rash or a stuffy nose. An allergy can also result in anaphylactic shock, which is life-threatening, but rare.
Various allergy tests can be used to identify the substance that is causing the reaction (allergen). Such tests include skin tests, blood tests, lung function tests, challenge tests and patch tests. Let’s take a look at them.
Allergy skin testing in Leesburg is used to assess for suspected environmental, food, stinging insects, and medication allergies. In this test, the suspected allergen is put on the patient’s skin and the results are studied after 15 minutes. Skin testing is done in two ways:
- Prick skin testing: Separate solutions containing the possible allergens are put on a person’s skin using a prick tool.
- Intradermal skin testing: Separate solutions with suspected allergens are put below the surface of the skin via a small needle.
An allergy doctor establishes which type of skin testing is necessary.
Along with a skin test, some people might need blood tests known as specific IgE tests to finish their allergy examination. Specific IgE tests may also occur in cases where allergy skin tests are not applicable. Such cases include:
- When a person can’t discontinue antihistamines or other specific drugs that can affect skin testing results.
- Person’s suffering from dermatographism (a condition in which scratching causes hives to appear).
- Patients with rashes or lesions that prevent an accurate reading of the skin test results.
Lung Function Tests/Spirometry
Lung function tests are specifically used to evaluate for asthma. During a Spirometry test, the patient is asked to breathe in deeply and then exhale forcefully into a spirometer. A spirometer is a device that measures lung function. That process is repeated at least three times for consistency in the results.
During a challenge test, the patient inhales or ingests minute amounts of an allergen under the supervision of a physician. Challenge tests are usually performed with suspected food allergies to establish the level of one’s allergy, particularly if skin or blood test results were inconclusive. They are also used to identify medication allergies.
In a food challenge, incremental doses of a suspected food item are administered to the patient beginning with a little quantity. Every dose is followed by observation and evaluation before taking the next dose. Upon receiving the last dose, a patient goes through an extra observation and assessment period. The same process is also used for medication/drug challenges. Due to the risk of adverse reactions, challenge tests are conducted under a doctor’s supervision.
A patch test is used to examine for an underlying trigger in a person who suffers from contact dermatitis e.g., getting a rash after putting on certain metal jewelry. The suspected triggers are put on the person’s back in the form of patches and removed two days later.
The process of searching for an allergy trigger is conducted in sequential steps. The first step is usually a skin test after consultation with a doctor. If the skin test is not appropriate, a blood test is performed instead. Challenge tests are only used if the skin tests or blood tests are unsuccessful.
Before you undergo a skin test, you should tell your doctor about any existing medical conditions related to your skin or lungs. Also, let them know about any heart issues. It’s essential to disclose any medication you’re taking that might affect your skin’s reaction e.g., amoxicillin, penicillin, aspirin or ibuprofen.