Vet question - sneezes

[Wolverine]

OK, our 13.5 year old elkhound has been sneezing lately. A LOT. These are true sneezing, not those creepy reverse sneezes that dogs do. It started several months ago, but has been really bad lately.

Some of these are really bad. I've seen a couple of times where she's sneezed so hard that she's knocked herself over. I know that excitement can do it, and she does a few sneezes when she's waiting for her food bowl or waiting to go out, but they also wake her up from sleep sometimes (and wake us up sometimes, which we're not thrilled about). She's also smacked her head pretty hard on furniture if she's too close when it happens.

She hasn't had changes to her daily routine or her food. We did move recently, but this started well before that. She's only exposed to our other dog; he hasn't been around many other dogs lately, and he hasn't had any problems.

She doesn't have any discharge or bleeding from either nostril, and her breath isn't any more foul than typical dog breath (and it hasn't changed at all); I don't think there's a foreign body. It's been getting slowly progressively worse. At times, she does sound a little stuffy just breathing, but not all the time. Her sense of smell has been declining for about the last year.

I know that dogs can get polyps, like we can. Is there anything that can be done about these if that is the cause?

From what I've read, allergies can very occasionally do this, but are more likely to cause itching, which she doesn't have.

I also know that tumors can do this, but, the fact is, at this point, with all the health problems she's had, and where she is now, I don't think we could bring ourselves to put her through surgery or chemo or anything drastic.

Anything else that would typically cause something like this?

Dave