I take a prescription drug - street name is NeoClarityn, (docs name i think is desloratadin or something).
Not related to clarityn, but it is one a day, and one prescription will last you all summer (cheap!)
Works a treat when benadryl - clarityn etc didnt, and a few docs tell me it is the only one the CAA approve. (It is actually used by NASA astronauts), as others which claim to be non-drowsy arent always (fruit juice ??)