Allergy prick test (skin prick test): benefits, process, and results

Function

What is the skin prick test for (skin prick test) done?

Skin prick test or skin prick test is a test to detect whether you have an allergy to several allergens at once or not. Some of the allergens that can be tested with this allergy allergy test are generally pollen, mold, animal dander, mites, or certain foods.

The skin prick test is a safe allergy test. However, this procedure cannot be done haphazardly. Only a specialist in the field of allergy-immunology (immunologist) can do this.

Allergy test results can be known only within 15 minutes after the test is done.

Precautions & warnings

What should I know before undergoing a skin prick test (skin prick test)?

This allergy test is safe for anyone, including children.

However, children who are allowed to take the skin prick test are at least 3 years old and in good health.

The skin prick test in children is carried out using a special needle so that the child will not feel pain or bleed.

Procedure

How is the skin prick test done?

The allergen extract used in this test is made from natural ingredients, which are ingredients that often cause allergic reactions in people. On skin prick test of this, the allergen used is very small in concentration. In one prick test test, more than 1 type of allergen can be given and a maximum of about 25 allergens.

This test is done by inserting the allergen extract onto the skin. The body used in this test is generally the inner arm. Here is a step-by-step how skin prick test done:

• The nurse will clean the arm with a cleanser containing alcohol and water.
• The skin of the arm is coded with a skin marker according to the amount of allergen tested. Each mark must be at least 2 cm away.
• The doctor will drop an allergen solution next to the mark that is already on the skin of the arm.
• The doctor will insert a sterile lancet needle into the skin that has been poured with the allergen. The lancet needle used for each skin prick test should be new
• If there is excess allergen solution, it will be wiped with a tissue.
• 20 to 30 minutes later, the doctor will observe the reactions that occur on the skin

Apart from using allergens the doctor will also test 2 other substances on skin prick test :

• Histamine will also be tested on your skin to determine the response in the body. If you don't react to histamine, it means you don't have an allergic condition.
• Glycerin or saline solution. In most people, this substance does not cause any reaction. If you react to glycerin or saline, you probably have sensitive skin, not allergies.

Preparation

What should be prepared before taking this test?

Before committing skin prick test , your doctor will check while asking your medical history. In addition, you will be asked about your symptoms, suspected triggers and lifestyle during the exam.

Later, this information will be used to determine what allergen extract was used in the test.

After that, there are some preparations that you must adhere to during the skin test. The doctor will tell you not to take some medicines before carrying out this test. The following drugs should not be taken, at least 10 days before an allergy test:

• Prescription antihistamines such as levocetirizine and desloratadine
• Over-the-counter antihistamines, such as loratadine, diphenhydramine chlorpheniramine, cetirizine, and fexofenadine
• Tricyclic antidepressant drugs, such as nortriptyline and desipramine certain heartburn medications, such as cimetidine and ranitidine
• The asthma drug omalizumab can interfere with test results for six months or longer even after you stop using it

Post-test care

What to do after the skin prick test or test?

After undergoing skin prick test , maybe you may feel some symptoms of an allergic reaction. Symptoms of an allergic reaction range from mild to quite serious, such as swelling, bumps, or itching. Severe reactions such as anaphylaxis can occur, but rarely.

Later the doctor will provide topical medication or ointment for allergic skin reactions. As for severe allergic reactions, the doctor will give you an epinephrine injection after the prick test.

The skin prick test is a safe procedure, it is only done in a professional hospital or clinic, and under the supervision of a specialist. So, all allergic reactions that arise can be treated immediately.

If you prove to be allergic to a certain substance, you will then be asked to avoid that substance to help prevent recurrence and reduce the risk of complications.

Dos and don'ts

What should be avoided after a skin prick test?

In general, you should follow these suggestions after and before taking an allergy test:

• Follow all the recommendations given by your doctor, including not taking allergy medicine before the test
• Not consuming any food or drink that is suspected to cause allergies and complications.

If you don't follow these precautions, it could possibly affect your test results and you may have to start all over again.

Test results

How do I read the skin prick test results?

The results of the skin prick test will be assessed based on the level of reactions such as redness, swelling, and the size of the bumps on the skin.

Allergic skin characteristics generally have a rash or rash with white edges, red in the center as a sign of a skin reaction. It usually takes about 15-20 minutes to reach the maximum size and after that the allergic reaction is several hours ahead.

The results of the prick test can be positive and negative. Skin prick test a positive result indicates that you may be allergic to a particular substance. Large bumps or redness on the skin, usually indicating a greater level of sensitivity.

If the skin test is negative, it means you may not be allergic to that particular allergen. From these results, later you will be directed to the drugs, diet, and lifestyle that will be recommended to treat your allergies.

But keep in mind, the results of the prick test are not always accurate. Sometimes this test will show false results. Suppose you are not allergic, but the test results are positive. This is referred to as (false positive).

An allergy test may also not trigger any reactions, so it can be referred to as (false negative). This condition can be caused by:

• You are taking drugs that block the effects of histamine
• The reactivity of your skin decreases, this usually occurs in infants and elderly patients
• Allergen extracts are too dilute (especially if given food allergens)

If the test results are in doubt, your doctor will likely recommend a repeat prick test and other additional tests to confirm your allergic condition.