I cant beleive it!!

my 4 ft hogg island is still sick! It has had a upi and mites in the past month. 2 visits to the vet and 400 dollars, a whole change in his setting later and he is still sick!! What should i do.. today i noticed his beathing is getting worse than before he was treated with baytril, there is also some swelling under his head when he breaths out it seems to swell.. kind of like a frog? his saliva is a little stringgy. WHAT SHOULD I DO!!! any one have a good vet to recomend on the south shore??