Things You Should Know About Allergy Skin Tests
You may have noticed every time you walk into your backyard, you start sneezing or sniffing. With this condition, people consider that they have an allergy. But they can't determine what they are allergic to. It can be the grass, pollen, or your neighbor's pet.
The only way to find out the reason for your sneezing is to have an allergy test. You should consult an experienced health expert to learn more about an allergy test. To know more about the test procedure and price, you can contact MyDiagnostics. Our expert doctors and technicians suggest you with the best tests for skin allergies.
Proceed through the post to learn more about skin allergy tests. Your doctor can do one or more of the several different types of allergy tests to determine the causes of allergies. The skin test is the most common thing to check whether you have an allergy. It diagnoses various allergy causes like animal fur, pollen, insect stings, and foods.
What is an allergy skin test?
Allergy is an overreaction by the immune system to something that doesn't bother most people. An allergy skin test helps to determine the cause of allergic reactions by exposing your skin to allergy-causing substances or allergens.
Our immune system is the main defense system of our body. It effectively fights germs. But if you have an allergy, the immune system faces a harmless substance, like dust or pollen, as a threat. Your immune system positively responds to this threat and causes an allergic reaction. The symptoms of the allergic reactions usually include sneezing, stuffy nose, or a life-threatening condition known as anaphylactic shock.
During an allergy skin test, your healthcare provider will expose your skin to a suspected allergen to check if you have an allergic reaction or not. Some of the substances that can cause allergic reactions include;
- Dust mites
- Pollen
- Molds
- Food
- Pet dander
- Medicines
- Insect bites and stings
- Household chemicals
The overreaction of an allergy is also known as a hypersensitivity of the immune system. Usually, there are four main types of overreactions including; Type I through Type IV hypersensitivities. Type I hypersensitivity causes some common allergies. The reasons behind this allergy are pollens, dust mites, foods, and animal dander.
Other types of hypersensitivities cause various types of immune system overreactions. You can experience mild skin rashes to serious autoimmune disorders. An allergy skin test usually finds out the causes of Type I hypersensitivity. The test also looks for reactions to specific allergens on the skin.
When is an allergy skin test performed?
Doctors recommend an allergy skin test if you experience allergy symptoms or asthma. These tests help to identify allergens that cause allergic reactions asthma attacks or severe asthma symptoms.
A doctor can recommend an allergy test if you have an anaphylactic reaction. It is a severe allergic reaction that develops quickly. With this condition, you will face difficulty in breathing. Without proper treatment, this condition can be deadly even.
You should know that no allergy skin test shows 100% accurate results. However, when an experienced healthcare provider performs these tests, the results will be helpful surely. Doctors review patient's medical history and if required suggest additional tests to confirm their diagnosis.
What are the three types of allergy skin tests and how are they administered?
There are three types of allergy skin tests that doctors usually suggest. Before attempting every test, your healthcare provider will clean the particular test area of your skin with alcohol or iodine. Usually, the forearm or upper back is the area for allergy tests. To perform the test with young children the healthcare provider applies a numbing cream.
The three types of skin allergy test name include;
Skin prick test
It is the most common type of allergy test where your body gets exposed to small amounts of possible allergens. This skin prick test helps to detect airborne allergies or food allergies. Doctors may also suggest this test as an initial test for stinging insect venom, penicillin, and other medication allergies and follow up with intradermal testing.
The healthcare expert uses a marker to label your arm with possible allergens. Then they use a thin needle to prick your skin near the labels with small amounts of liquids. This liquid contains different possible allergens. However, the lancet won't go deep into the skin. Usually, it feels like a tiny pinch.
In some cases, droplets of possible allergens are placed on your skin, and use a lancet to scratch the skin surface gently. The droplets enter the skin through the scratch. In specific cases, the healthcare provider can also apply positive and negative controls on your skin. It helps your provider to compare reactions.
A positive control comes with a histamine solution, that causes an itchy, raised spot on the skin shortly after exposure. A negative control has a saline solution that won't cause wheals to develop. After this test, you have to wait for about 15 minutes. Then the provider will check for any discolored spots on the skin with a ruler. A skin prick test usually takes less than an hour.
Patch test
During a patch test, a healthcare expert applies patches on the skin that contain possible allergens. It helps to determine the cause of contact dermatitis. The doctor will first ask you what kind of lotions, soaps, makeup, and jewelry you use.
The healthcare provider will customize patches of possible allergens that stick to your back. You need to leave the patches on for two to four days. Then your provider will remove the patches to check for allergic reactions.
Intradermal test
During an intradermal test, a tiny needle is injected into the outer part of the skin to find out the possible allergies. Healthcare providers use intradermal tests to check whether you have any airborne allergies, insect allergies, or medication allergies.
The healthcare provider uses a marker to label your arm with possible allergens. Then they follow two more stages. In the first stage, the provider inserts a small amount of allergens under your skin, next to the labels. Then you need to wait around 15 minutes before the provider measures any wheels or discolored spots on the skin.
- If you test positive for a specific environmental allergen, you won't need additional intradermal testing.
- If you test negative for an environmental allergen, it means you are not allergic to that allergen and you don't need any further testing.
- If you test negative for a particular medicine, you should move on to a second intradermal test.
- If you have a negative result for stinging insect venom, you need to go for three more sets of intradermal tests. You should know that each test will be a little stronger than the previous test.
An intradermal test is not very painful and it is even less painful than the skin prick tests. This type of test usually takes around 60 to 90 minutes to get done.
FAQs
What is the most accurate skin allergy test?
The skin prick test is the most accurate test to diagnose allergies. This skin allergy test causes an immediate reaction.
Can a blood test detect skin allergies?
Yes, allergy blood tests can detect skin allergies. These blood tests are reliable for diagnosing allergies to airborne substances such as pet dander, pollen, and dust mites.
How do doctors test for skin allergies?
In most cases, doctors do prick or scratch tests to diagnose skin allergies. In this test, a small drop of a possible allergen is pricked or scratched into the skin.
