DR. J. OHAYON - ALLERGY & IMMUNOLOGY CLINIC

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For five (5) days before your appointment, you must discontinue antihistamines and over-the-counter cough, cold, or flu medications.  If there are concerns discontinuing your antihistamines, please contact our team  .


You MAY continue using asthma puffers, allergy nasal sprays and steroid creams.


If you are on beta-blocker therapy, you will require permission to hold your beta-blocker for (1 to 2) days PRIOR to your appointment. YOU WILL NEED TO RECEIVE APPROVAL FROM YOUR FAMILY DOCTOR FOR TO WITHHOLD YOUR BETA-BLOCKER medication.


A medical consultation can be arranged, if you are unable to hold allergy or beta blocker therapy.  Please keep your appointment and Dr. Ohayon will  review your medication status with you.

Preparation for Appointment

The appointment will be at least 1½ hours.


Cancellations must be made more than 24 hours prior to the appointment time so that we can offer your time to someone else. . All missed appointments will be subject to a fee.

The Appointment

Our clinic has samples of most allergenic foods. However, you may be requested to bring a sample of the suspect food to contribute to your investigation. Please keep your food frozen until your consultation appointments.

Food Protein Testing

Assessments and Skin Testing

Please be aware there will be a $40 fee for preparing the necessary testing reagents for antibiotic allergy testing and in office challenge.  We accept cash, VISA, or Interac.


In certain situations of suspected medical allergies, a prescription may be needed at a compounding pharmacy to prepare.  


Our office works with many pharmacies, including Marchese. Specialty pharmacy.  You may be asked to contact Marchese at 905-528-4201 several weeks in advance of the appointment to discuss payment for the  preparation of your medication for allergy testing .

Medication Testing

Skin prick testing is usually conducted on the arm. If unable to test on the arm, the back may be used. Please dress appropriately so that we may have access to the arm or back for testing.


At the site of the prick you may develop an allergic reaction, like a mosquito bite, that will be itchy and red. This reaction is usually short lived and does not require any treatment. Rarely does skin testing lead to systemic reactions, i.e., sneezing, coughing and/or wheezing, but this may happen. If these reactions are identified, medications in our office will be used promptly to reverse your allergic response to testing.


Note that developing an allergic type skin  reaction alone may NOT be indicative of allergy. All patients will be tested to our “controls” where we expect to see both negative allergic response (to saline) and positive allergic response to histamine.  Your history and physical examination when meeting with Dr. Ohayon  is key in determining the medical relevance of your skin test  responses.


The Skin Prick Testing Procedure