Thank you for your inquiry.
There is no definitive answer to either question that you asked. I believe that you would get many different opinions if these questions were asked to allergists across the country.
The rationale for holding the dose during pollen seasons is that there tends to be an increased risk for reactions during this time, but to my knowledge there are no studies that have compared outcomes in terms of efficacy versus reaction rate between holding the dose or continuing with dose progression during the pollen season. Thus we have no objective data, at least to my knowledge, to allow us to make an evidence-based decision. There is no mandate to hold the dose during the pollen season, and the decision to do so is left to the discretion of the treating physician. I personally do not hold the dose during pollen season.
There is also no "established youngest age" as to when one skin tests either for epicutaneous testing or intradermal testing. It depends on the clinical situation, but we do know that intradermal tests can be safely done in children under the age of 1 year. I have seen allergists who performed intradermal skin tests under the age of 1 year based upon their perception of need, and we also have allergists who do not do intradermal skin tests in children at all. So, the decision as to the utilization of intradermal skin tests in infants is like the decision to hold dosing during the pollen season - it is left entirely to the discretion of the allergist caring for the patient, and there are differences of opinion in this regard.
Thank you again for your inquiry and we hope this response is helpful to you.
Phil Lieberman, M.D.