What is an Allergy test and its Types: Allergies are common issues that are faced by almost every living being. Many types of allergies related to food, sunlight, or any other material can cause various forms of irritation.
The treatment of allergies can be easy however, sometimes it may get worse for a person who has a severe intolerance towards an allergic substance. To determine the allergies and their causes, an allergy test is conducted by healthcare providers. Let’s understand the details about the test for allergies.
Allergy Blood Test: Details
An allergy test is conducted to measure and detect the allergen-specific antibodies that are present in the blood. This test is prescribed to the individuals in the following cases:
- Symptoms like sneezing, itching, swelling on the body, redness, or stuffy nose. This can happen because of exposure to an allergen.
- To determine the most common allergy that can be caused due to grass, weeds, nuts, molds, trees, pet dander, dust, and shellfish.
- Individuals having skin conditions like eczema or psoriasis
- Individuals facing conditions like anaphylactic shock.
- To test the results of the treatment of the allergy.
- Individuals having an unstable heart condition or poor asthma.
However, for testing the allergy, there can be many ways. It includes a blood test, skin test, elimination diet, and more.
Allergy Blood Test
This test is conducted by taking a blood sample. It measures the amount of IgE antibodies in the blood. IgE antibodies are produced in the blood because of allergens. This type of test is also known as the specific IgE test. The Allergy Blood test can be performed in the following conditions:
- Patients having skin rashes.
- Patients experiencing the condition of dermatographism.
- Patients consuming antihistamines or any other medication that affects skin test
There are two components of the Allergy Blood Test:
- Enzyme-linked immunosorbent assay (ELISA, or EIA)
This component helps to determine the amount of allergen-specific antibodies in the blood.
- Radio allergo sorbent test (RAST)
This test helps to determine the specific allergen-related antibodies. With this, a doctor can identify the triggers that are causing allergies in the body.
Allergy Skin Test
Apart from the Allergy Blood Test, sometimes doctors prescribe the allergy skin test to the patient. In this type of test, no blood is taken from the body. The test can be easily conducted by putting the allergen on the skin. For the next 15 minutes, the results are then observed. However, there are two ways to do this allergy skin test. It includes pricks skin testing, and the other is Intradermal skin testing.
In prick skin testing, the allergen is left on the skin, and then the results are analyzed for 15 minutes.
While in the Intradermal skin testing, the allergen is injected into the forearm skin. After which results are analyzed for 15 minutes.
In patch testing, it is tested whether the allergies are caused due to any contact dermatitis. On a patch of skin, the suspected agent is placed, and then it is left for at least 48 hours. The agent is removed after 48 hours, and then results are observed. Sometimes the findings are observed for 2-5 days but, sometimes it may extend to 10 days.
Food Challenges or Elimination Diet
This type of allergy test is prescribed by doctors when a patient is suffering from any food item. In this test, either the food dose is increased or decreased. The dose of the food is increased, and with every quantity increase, the doctors observe the result. This is continued for a small period. After the final dose, the observations and an assessment are made.
As there is a high chance of adverse reactions on the body, it should be done under the supervision of a physician. Apart from this, in the process of the elimination diet, the food products are eliminated from the diet. It can be done by excluding food products or avoiding suspicious food products.
Drug or Medication Challenge
This test is prescribed by doctors to test the allergies caused by any medication. However, it is done on selected individuals only. In this type of test, the process includes the increment in the dose by a small amount initially.
Like the food challenge, here also, observations are made after each dose of medication. When the final dose of medicine is given to the individual, he/she undergoes additional assessment. This test should be performed under the supervision of physicians only as it can create adverse effects on the body.
Allergy is a natural or hereditary issue that can be caused due to many reasons. Some reasons can be common, while some can be unique to the person. It is important to treat allergies as they can cause various other issues in the body. Therefore, testing for allergies is the first and best step towards the same.