Okay I have a question...someone said taking Benadryl and then taking Zyrtec doesn't really work.

My son takes daily Zyrtec for pollen, seasonal allergies (except it is fl and we don't have seasons it is generally year round)....we go visit grandma and she has a cat...he adds a Benadryl to the Zyrtec for a few days and can function without clawing out his eyes and sneezing constantly.

So b then z does no good but z then b can add to the therapy?