The Allergy scratch test is a test to see what foods, medications, plants, dust, animals, or molds the person is allergic to. They check for a skin reaction to a protein that can signal to the doctor what items the person is allergic to. Once the allergy test is over, roughly half an hour after it began, then your doctor will be able to tell you if you were allergic to any of the items in the allergy scratch test panel that day. You will not have to wait.
Preparing for the Allergy Scratch Test
When you make the appointment for the allergy scratch test, give yourself at least three to four days to go off any antihistamines you currently are taking for hayfever, allergies, or other sniffles. Taking antihistamines too close to the testing can disrupt the test and give false negatives.
Also, make sure that the doctor that is doing the allergy scratch test knows if you have ever had a reaction to a different allergy test in the past, or if you have ever had a severe allergic reaction so bad it went into anaphylaxis. This type of reaction is so severe it can be life threatening, so your doctor will need to know what things trigger that type of response in your body.
Realize that if you have any positive reaction in the allergy scratch test that the area that reacted will be red, possibly a little swollen, and itchy/warm. This is going to feel similar to a bug bite and you will need to treat it as such with antihistamines and keeping the area clean with antiseptic.
How the Allergy Scratch Test is Done
At the time of the appointment, you and your doctor will discuss your lifestyle and any past allergic reactions. You will come to an agreement as to what items will be tested for allergies. If the test subject is a child, the test will be given on the back; if an adult, on the forearm.
Fluid will drop on to the skin in certain areas and the doctor will make a small scratch, not even deep enough to draw blood. The prick to the skin is just to get the fluid under the skin surface.
You will have to stay still for up to a half hour to wait for a reaction. After this time your skin may itch, but you must stay as still as possible. Once completed, your doctor will see if there is any redness or swelling and if so, you have a positive allergy test for the protein that was dripped into that area.
You may get an allergy test for a few or for quite many different proteins at one time, the choice for the amount and for which proteins will be made by you and your healthcare provider.