What medications are antihistamines and why must I stop taking antihistamines ten (10) days prior to my appointment?

To make certain that you can be allergy skin tested at your visit to Allergy & Asthma Specialists, do not take any antihistamines ten (10) days prior to your appointment. Antihistamines block the skin testing results and the physician will not be able to determine how best to treat you. Antihistamine medications include Allegra, Claritin, Clarinex, Zyrtec, Alavert, Loratadine, Phenergan, Atarax and Astelin (a nose spray). Some over-the-counter medications such as Benadryl and allergy/cold/sinus medications can be taken up to 3 days before your allergy testing. At your visit, the physician will assess if any of the above medications, if taken, will interfere with skin testing. If it is determined that skin testing results will not be accurate, you will need to reschedule your appointment.