Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
Perhaps, your vet gave Baytril injections in the hospital, saw improvement and assumed this category of antibiotic would work (however she might have improved more from the fluids than antibiotic). Zenequin (marbofloxacin) is in the same category as Baytril (enrofloxacin) and certainly "safer" longer term for a course of treatment in cats. So, they are essentially the same thing although slightly different within the same category. I agree if she had a previous infection and it didn't respond to zenequin then I do not understand why the use of baytril and not turing to a completely different category of antibiotic for her.
If your vet was worried about infection which might suggest kidney infection then is there a urine culture pending? This is very important, and if not already done then when she is rechecked in 2-3 weeks for her urine then a culture at that time would be advisable to rule out persistent infection. This is even more important since she has had multipole rounds with this antibiotic (zenequin) an therefore might have a bacteria which is resistant, especially if this is an E. Coli infection which are notoriously resistant to this category of antibiotics.
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