Oh thank you
It's actually a bit of a relief to find it could perhaps be hay fever. was beginning to wonder if he had some chronic illness that wouldn't clear up.
Button weighs 7lb, so I could try the Benedryl, though perhaps I should pop him back to the vets first to be on the safe side with diagnosis. At least I can suggest it might be that now, as I don't think his vet had considered that possibility.