8-year-old Yorkie/shih tzu wheezing

Question
My 8-year-old Yorkie/shih tzu cross has always been allergic to one particular pollen. Fortunately, it's one that she doesn't normally come across unless she goes through a field of it, usually in about August. The symptom is wheezing.

At the start of this month, she began wheezing again. She doesn't have any signs of a chest infection, and doesn't have any other symptoms. I can't think of anything she could be allergic to in March, and her surroundings are unchanged. It's no colder than usual. It's been going on for nearly 3 weeks.

She weighs 4.7-5.9kg. I've treated her adequately with 2mg piriton once per day.

The reason I write is that I could do with a possible cause and a long-term solution. I can't afford to see the vet.

What's the most serious condition it's possible for it to be? Can you suggest anything else to help?

Answer
Quite perplexing. I'm sorry, but the only suggestion I can provide is that you at least call your vet and get a consultation. It doesn't cost to talk through the phone to him/her, and it may be very helpful. Also, if possible, try to find another veterinarian in your area that you can afford. I'm sorry I have no other suggestions.

Hope this helps!
Katie