A nurse is reinforcing teaching with the guardian of a preschooler who has heart failure and a prescription for furosemide. Which of the following instructions should the nurse include?

A. "Administer the medication early in the day.": Furosemide is a loop diuretic that increases urine output. Giving it early in the day helps prevent nocturia and sleep disturbances, ensuring the child remains well-rested while still receiving the therapeutic effect of fluid removal. B. "Restrict foods that are high in potassium in your child's diet.": Furosemide can cause potassium loss, so the child’s diet should include potassium-rich foods rather than restrict them. Adequate potassium intake helps prevent hypokalemia, which can cause muscle weakness, arrhythmias, and other complications. C. "Anticipate that your child will gain weight rapidly while taking this medication.": Furosemide typically reduces fluid retention, which may lead to weight loss or stabilization, not rapid weight gain. Rapid weight gain would indicate fluid accumulation or worsening heart failure, requiring further evaluation. D. "Expect your child's urine to appear concentrated and dark yellow.": Furosemide increases urine output and dilutes the urine. Urine is more likely to be pale or clear rather than concentrated and dark yellow unless the child is dehydrated or not adequately hydrated.