Welcome! My name isXXXXX am a 2003 graduate from UC Davis, and currently a Medical Director of a veterinary hospital.
I am sorry to hear about this concern for Mimi.
Well, there is no question that the presence of a urinary tract infection, in itself, can alter urine pH, as well as, any drugs that are excrete through the kidneys can impact it as well.
Now, for whatever impact the antibiotic would have is short-lived, because once the antibiotic is out of the pet's system, the urine pH would return to whatever it was before infection and treatment.
The real question is what impact is the food having on the urine pH. Diet plays
a huge role on urine pH and can swing it to being very alkaline (basic) or very acidic. Enough so, that just what you feed can predispose to bladder stones forming.
So, always wise to re-evaluate the urine about 7-10 days AFTER ALL the antibiotic is finished to see what is going on and to ensure the infection is eradicated.
I hope that information has been helpful.
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