Welcome to BB and I’m sorry to hear your baby is unwell. It’s good that only one seems to be showing signs and you don’t have two snotty rabbits on your hands!
I would explore the option of a different medication with the vet if you see the sneezing is getting worse or has plateaued to a point that is interrupting your rabbit’s well being. Baytril is one of many medications used to treat upper respiratory infections, and it could be that the specific infection your rabbit has isn’t one affected by Baytril. I will also mention that a 1-week course of medication is usually too short. Many URIs are not treated or come back later as a result of stopping medication too soon. Imagine the bacteria only needs one of itself to multiply, but one isn’t enough to show sneezing symptoms. A lot of time, people will stop medication when there are no symptoms, but this allows that one bacteria to remultiply and show symptoms later, thus the cycle continues.
It took three medication trials over a continuous five month treatment period for me to cure Wick. We started with 2 weeks on Bactrim, no results. Then we did 3 months on Baytril, with some improvement but not completely gone. Then we did a month of Baytril plus penicillin shots. This did the trick miraculously! No more sneezing!
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.