A 3-year-old child weighing 14 kg has a nitrofurantoin suspension dose of 10.5 mg four times daily for 7 days for an acute urinary tract infection. Three days later the mother reports the child’s urine is yellow-brown. What is the most appropriate advice to give to the mother?

• A. The urine color change is harmless; continue therapy
• B. Seek emergency care
• C. Stop therapy immediately
• D. Switch to another antibiotic

Answer: (C)

A change in urine color during nitrofurantoin therapy can indicate a potential adverse effect that needs prompt action. While nitrofurantoin often turns urine a harmless brown or dark yellow, a yellow-brown discoloration, especially in a young child, can raise concern for possible liver involvement or other drug-related toxicity. Because early stopping and medical evaluation can prevent progression of a serious reaction, the safest course is to stop the medication now and seek medical advice to assess liver function and determine an alternative treatment for the UTI if needed. If evaluation is normal, another suitable antibiotic can be considered for the infection.