You'll probably be given a prescription for antibiotics in liquid form, with instructions to give your baby between one and four doses a day for up to two weeks, depending on the drug.
Even if your baby starts to seem better in a few days, continue giving the medication until it's gone. If you don't, the bacteria causing the UTI might not be completely wiped out and the infection could come back stronger, making your baby even sicker.
If your baby is very ill and unable to eat or drink, he'll need to spend a few days in the hospital so he can receive medicine intravenously. Babies younger than 30 days old with UTIs typically need to be hospitalized for treatment.