Should my 21-year-old daughter switch to a different antibiotic for her third urinary infection in 3 months? Why does the infection keep coming back?

It is possible that your daughter's recurring urinary tract infections may be due to the bacteria in her urine becoming resistant to the antibiotic she has been prescribed. It is important for her to see a doctor for further evaluation, including a urine culture, to identify the specific bacteria causing the infection and choose an appropriate treatment. In the meantime, she should follow basic hygiene practices such as wiping from front to back, staying hydrated, and urinating after sex to help prevent future infections. If the infections continue, she may need more advanced testing and treatment.