Is the only treatment for a uti in a toddler antibiotics? Grandbaby has been dealing with a fever on and off for the past two days. (Fever was102.2 at one point, but parents are not using fever suppressing meds.) No other symptoms; however she had been constipated, and i know that can cause a uti. She is unvaccinated, still breastfeeding a bit, and eats no processed foods.