In case the clip above loads slow, you can watch it at YouTube here: What you should know about Skin Prick Test
Skin prick test is one of the many procedures an Allergist Immunologist perform to test for allergic sensitization.
- It does not hurt
- It is accurate
- And you can get results in 15 minutes
One of the tool used for allergy skin prick test is called the allergy pricker. The video above will show you what the allergy pricker looks like. It simply scratches the surface of the skin to allow for the allergens to enter the surface of the skin to cause a reaction that we can observe and measure. It does not hurt and it does not fully penetrate the skin and it does not cause any bleeding.
Do you reuse the skin test tool?
With each skin test, a new skin pricker tool is used and the used pricker is disposed. Patients sometimes think that we reuse the allergy pricker tool, we want to reassure you that this DOES NOT happen, and that the Allergy Immunology Clinic follows the highest standards of practice for your safety.
What do all the numbers mean?
At the end of the 15 minutes, we will measure the swelling called wheal and the redness called erythema. You may see the number written as 5/15 which means that the swelling is 5mm in diameter and the redness is 15mm in diameter. There will be a scoring system next to the measurement from 1+ to the maximum of 4+. The scoring system is based on the positive control. If it is the same size as the positive control it will be rated 3+, anything larger and smaller will be scored accordingly.
What does the Histamine mean?
Some patients may see the positive control listed as histamine and they ask if it means that they are allergic to histamine. Not so! Histamine is released during an allergic reaction and we use a standardized histamine reagent to mimic what a positive reaction should look like. Having a positive reaction also means that there is no antihistamine medication still working in your body and that the test is valid. We also compare your tests to the negative control as sometimes the skin may be sensitive and swell up with a scratch stimulus.
You can learn about how skin prick test is done.
You can read more about skin prick test and what medicines can or cannot be taken before skin prick test.
Why didn’t you tell me to stop my medicines before coming for my appointment?
It is important to know that when you schedule your first appointment with us at the Allergy Immunology Clinic, we do not usually tell our patients to stop any medications prior to their visit. This is because without a full consultation, we will not know what is the best testing modality or if any testing is needed. It is also unsafe to tell you to stop your medications without knowing your full medical background. We will always recommend that you see your doctor first for a full consultation prior to any decision on testing or treatment.
