Pet Allergies

My poor pup has developed allergies.  I don't know yet what he is allergic to, but he is scratching his face off.  It's only been a few days, but I am getting concerned.  We haven't changed his food.  He's on Frontline and Interceptor, all that good stuff.  I washed his crate bed (and no, I haven't changed our laundry detergents or anything like that.  We already use additive free stuff for Justin's sensitive skin.)  I am thinking of giving him a bath although it hasn't been 2 weeks since I put the Frontline on him.  It's either that or Benedryl.  

I had done some reading online and it appears plenty of people are giving their pets, at the recommendation of their veterinarians, Benedryl for seasonal allergies.  A family member who also has three dachshunds has told me that her vet has given the ok to give two of the pink adult Benedryl pills (not the tabs/capsules) and it seems to help.  I'm just a little nervous, even though our vet had mentioned Benedryl to us a while back.

When we'd first gotten Riley, he had a little soft pallet issue that would cause him to wake up from a dead sleep snorting for air.  It was pretty scary.  I took him to the vet right away and she said it could be one of two things: a.) a preexisting condition, or b.) a reaction to an allergen.  Of which three things were available: a.) surgery to correct the situation if it persisted, b.) 1 tsp of Children's Benedryl, or c.) make him give kisses or rub his throat when it happens and hope he grows out of it.   Well, we opted for the third option since the pallet thing wasn't happening all the time.  We figured it was a reaction to an allergen but were a little worried as to the reaction he'd have to taking Benedryl.  The vet said it could either knock him out cold or have him bouncing off the walls, which as new puppy parents already getting very little sleep this was not a risk we wanted to take.

So... we have yet to medicate the poor baby and I am *this close* to just mixing it in with his food.  

Anyone else have similar experiences?  Want to share your solutions?