Retic Blisters and U.R.I.

Question
I have a 7 month old reticulated python that since February caught upper respiratory.  I brought it to a vet hospital and they gave it baytril shots total of 3 shots every 72 hours.  She got better than two weeks later started up with the symptoms again.  Went back to the vet and they did the same procedure 3 shots this time every 48 hours. Again okay for two weeks.  Then starts up again this time much worst where her sneezing wakes me up at night.  Went back to the hospital and they gave her baytril shot every 72 hours for a total of six shots.  It hasn't done anything now the snake has 5 blisters bumps on her body.  I made an appointment for her this Friday to another vet clinic to see what they say.  Have you seen or heard of this before? I checked online to see what cause blisters the websites say mites or contact with heat source. I haven't seen mites, and she doesn't get too close to the light, someone I work with said it happened to her cat that she said if the injectable was not given right it can cause blisters.  The blisters are not open sores just big bumps looks like something growing under her scale I touch them she shakes in pain.  I took all her logs out so she doesn't scratch or get cuts it open from the bark.  All she has now in the tank is paper towels as substrate, water bowl, and hide away I took a large blue tubberware container and cut a hole into it.  I'm just really worried will the blisters cause permanet damage to her body?  Is their anything I could put on the blisters until Friday the Vet visit like something topical to help?  She still eats like a champ.

Info of the snake
7 months estimate age and 3 1/2ft long female reticulated
lives in a 6 foot by 4 foot tank, custom built
humidity 60 to 70%
temperature 95 on the one end.

Answer
Baytril causes the blisters (hate it), and IMHO is worthless against RI in Boids (boas and pythons), does work pretty well in colubrids though.  Treat the blisters with Neosporin.  Ask the vet for an antibiotic called Amakacin (not sure if I spelled that right) it works great on RI in pythons.  If they won't do that find out what other options they have besides Baytril it simply isn't effective in boids not sure if it a metabolism issue or what but I gave up that drug a long time ago.