Allergy, Common ragweed
The pollen from the ragweed plant can cause allergy symptoms in many people, such as sneezing, a runny nose, and an itchy throat. It can also trigger asthma flares and seasonal allergic rhinitis (also called hay fever) in some people.
Ragweed is a type of weed found predominantly in the Eastern and Mid-Western United States. It blooms during the early fall months (between August and November), producing a yellow, powdery substance called pollen.
A common ragweed allergy test measures the IgE antibodies in the blood that develop in response to the ragweed allergen and helps detect an allergy
Symptoms of Hay Fever
Some of the common symptoms associated with seasonal allergic rhinitis or hay fever include the following
Sneezing
Runny nose
Nasal congestion
Headache
Irritated eyes
Itchy throat
Test preparation
This test does not require any special preparations.
Interpretation of the Test Results
The relative amount of IgE antibody present in the body in response to common ragweed allergy is indicated in the following table:
|
Class |
IgE kU/L |
Interpretation |
|
0 |
<0.10 |
Negative |
|
0/1 |
0.10-0.34 |
Borderline/ Equivocal |
|
1 |
0.35-0.69 |
Equivocal |
|
2 |
0.70-3.49 |
Positive |
|
3 |
3.50-17.4 |
Positive |
|
4 |
17.5-49.9 |
Strongly positive |
|
5 |
50.0-99.9 |
Strongly positive |
|
6 |
> or =100 |
Strongly positive |
Deviations from normal levels in the result may mean the following:
· There are increased chances of developing an allergy if IgE antibodies are present in the serum, i.e., Class 1 or greater.
Increased levels of total IgE indicate that you may have an allergy to common ragweed
FAQs
Is ragweed allergy associated with oral allergy syndrome (OAS)?
Sometimes, an individual who is allergic to ragweed may also show symptoms of oral allergy syndrome, or OAS. The immune system of such a person confuses ragweed pollen with certain kinds of food, such as watermelon, zucchini, bananas, cucumber, cantaloupe, and honeydew. As a result, when these foods are consumed, the immune system will react and produce an immune response. Such individuals are likely to suffer from itching or swelling of the face, mouth, or throat
What is the turnaround time (TAT) for this allergy test?
The turnaround time for the test to detect allergies to common ragweed usually takes about 7 working days. However, it can sometimes take a bit longer for the results to be obtained
How is the sample collected for IgE antibody testing for common ragweed allergy?
For blood sample collection, a small needle is inserted into a vein in your arm, and the required amount of blood is drawn. Usually, this procedure does not take more than 5 minutes
What are some of the risks associated with this test?
Since this test involves inserting a fine needle inside a vein in your arm, there might be slight soreness or tenderness at the site of injection. On very rare occasions, the site might get infected
How does one prevent common ragweed allergy?
The simplest way to prevent the common ragweed allergy is to avoid going to places where it is present. However, there are times when people accidentally come into contact with allergens and may develop symptoms. Therefore, if a person is allergic to a specific substance or thing, it is recommended that they carry their respective medications with them wherever they go
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