Snuffles - is Sulfamethoxazole/Trimethoprim safe?

Question
Hello!
Thank you for any advice you can offer me. Our rabbit was prescribed Sulfamethoxazole/Trimethoprim and I'm concerned about the safety and effectiveness of this medicine and I'm reluctant to start the course.

Our generally very healthy, happy 7 year old bunny recently came down with snuffles. Nothing out of the ordinary going on, hes never been sick outside of the very infrequent digestive issues.

We had him to the vet within a day, he listened carefully for possible pneumonia, looked at a nose swab and saw elevated white blood cells, and put him on Baytril for a respiratory infection. His nose and eyes cleared up right away and his appetite and behavior returned to normal. One week into the treatment, we missed one evening dose, and the next morning when we gave his dose, we noticed some nasal discharge, which is something we'd never seen before the snuffles. Later on that afternoon he also sneezed with a bit more coming out. At that point I spoke with our vet again, we talked it over, and he thought we should finish the antibiotic (at the time I thought we only had a few doses left) and see how things looked. This was Monday

This morning while we gave his Baytril (there was more left than we thought!), he had a big glob in his nose. We were really concerned about why this symptom kept returning despite the antibiotic and talked the the vet again. He said that the Baytril should have worked by now, and prescribed the Sulfamethoxazole/Trimethoprim.

I'm now reading a few sources that seem to say that this medicine isn't effective, could be harmful, may make the infection worse.. I'm feeling really torn. I'm thinking of going to another vet I used and loved in another city about an hour away tomorrow morning. He has absolutely no other symptoms other than this occasional thick white nasal discharge.   

Do you have an opinion? We'll do anything to help him. Thanks again for your time!

Answer
Dear Heather,

The potentiated sulfa antibiotics are pretty old, and this means that many bacteria are now resistant to them.  It doesn't mean they won't work for your bunny's infection, and they should be quite safe.  It can't hurt to try.

Has a deep nasal culture been done to identify the pathogens?  Please see:

www.bio.miami.edu/hare/culture.html

and

www.bio.miami.edu/hare/sneezing.html

for more information.

Many rabbits suffer from chronic schnucky noses because of blocked maxillary sinus caused by intrusion of molar roots or other obstruction.  In such cases, palliative care can sometimes be the only thing you can do short of a drastic, surgical procedure (rhinotomy) to open the blocked sinus.  But that would be extreme, and I doubt your bunny is a candidate for such a radical procedure at this point.

Be sure your vet is rabbit-savvy.  You can check the lists linked here:

www.rabbit.org/vets

to find the rabbit-experienced vets in your area.

Hope this helps.

Dana