Skin Testing
A quick procedure used to diagnose environmental, food, and medication allergies.
Appointments
Here's what to expect at your appointment. Click on each tile's title for a more detailed description.
Asthma Testing
Please bring all asthma medications and aerochambers to your appointment.
Patch Testing
This test is used to determine if you have a contact allergy. Please refrain from showering and strenuous activities that may cause excessive sweat until you return to clinic.
New patient appointments by referral only
New patients, please email back the filled new patient appointment information form prior to your appointment, along with the name and fax number of the pharmacy you prefer. Our email address is tsaiallergy@gmail.com (this is an unsecure email as it is not encrypted).
Skin Testing
The duo-tip is quickly pressed against your lower inner arm. This may also be done on your back.
After waiting in the office for 10 to 15 minutes, the doctor will check your arm.
If you are allergic to any of the allergens, you will develop a welt (raised itchy bump). The doctor will then measure its size.
-
I am coming in for testing to food, and I was asked to bring a small piece of food I am allergic to. Will I have to eat it?
No. For food skin testing, fresh food provides the most accurate results. Note that you do not need to bring in items such as tree-nuts, peanuts, milk, eggs, soy, or wheat. -
At what age can skin testing be done?
Under the age of 1 can be tested, however it can be less accurate. For children under 3, they have not seen enough seasons to develop seasonal allergies. Therefore, their skin test would only involve perennial allergies, such as dust mites, pets (cats, dogs etc.), and mold.
Occasionally, we do need to use a further type of skin testing that involves injecting pharmaceutical allergen extracts. It is a quick test where a small amount of the allergen is injected between the top layers of skin (inter-dermal). A small raised area will form (a bleb). This test only takes 15 minutes to get results.
Asthma Testing
You will be asked to blow into a tube, a nd the machine will measure a number of different things about your lungs. Occasionally, you may be given Ventolin (Salbutamol), and then asked to perform the test again. This test will help you and the doctor decide what is best for your asthma management. You will also have the opportunity to learn proper inhaler technique.
Patch Testing
Patches (like stickers), are applied to your back, and then you return to clinic after 72 hours to see if you are allergic to any of the allergens applied to your back.
See links below for complete information.
Food and Medication Challenges
Expect to be at the clinic for the full morning. You should come prepared with things to do, such as reading material, games, homework, etc. For food challenges : You will need to bring the food already prepared (i.e. peeled and sliced, nuts out of shell, foods cooked). For younger patients, you may need to bring items that will appeal to their eating habits (like ketchup, sauces they have eaten before, chocolate covered nuts, etc). For medication challenges : Please bring the medication as prescribed by the doctor. You are allowed to bring small snacks and drinks, however they must be consumed in the challenge room. If you have any questions, we encourage you to ask.
-
What happens at this appointment:
When you first arrive, the doctor / nurse will talk to you, check your vital signs (blood pressure, pulse, etc.), and check your skin to obtain a baseline. Please notify the doctor / nurse, before they start if you are taking heart medications such as beta-blockers or ACE-inhibitors. Once you are cleared to start: Food Challenges: The nurse will give you a small amount of food. After 20 minutes, as long as you are okay, you will be given a slightly larger amount. This will continue, as long as you are still feeling well, every 20 minutes until the prescribed amount of food as been ingested. Medication Challenges :The nurse will give you a small dose of the medication as prescribed by the doctor. As long as you are feeling okay, the next prescribed dose will be given in 30 to 45 minutes.
After you have had your last dose, you will be required to wait in the office for 1 hour , and after this time, the doctor will check to ensure you are clear to go. -
What if I have a reaction?
If you have a reaction, the doctor and nurse will treat you in the clinic.
Our office is equipped to treat any anaphylactic emergency , so there is no need for you to use your own EpiPen / medication.Click for the Food Challenge Information sheet.
Special Clinics
Each month we run separate clinics for Penicillin and venom (stinging insect) allergy testing. These clinics involve a lot of preparation by all of our staff and are costly. It is important to attend your appointment as scheduled. If you are unable to do so, you must give at least 48 hours notice . Otherwise, you will be charged an $85 no show fee, and will not be booked into future clinics until this fee is paid.
It is important that you call our office to confirm attendance to your appointment. If there are not enough confirmed patients, the clinic will be canceled and re-booked.
Please see the information sheet regarding these clinics (cancellation within 48 hours of these appointments results in a $85 no show fee):
Penicillin Clinic.
Note that there is a $50.00 fee for this clinic, not covered by OHIP, payable at your appointment.
For these appointments, it is important to note that testing will be done using a series of needles. Because it can be quite uncomfortable for our younger patients, please consider using EMLA patches. These should be applied to the patient's upper, outer arm (just below their shoulder), about 2 hours prior to their appointment. The nurse will remove the patches prior to testing.