An infant with congestive heart failure is receiving digoxin (Lanoxin). What does the nurse recognize as a sign of digoxin toxicity?

A. Increased urinary output: This may indicate improved renal perfusion or diuresis, not toxicity. B. Vomiting: Vomiting, especially without other explanation, is an early and common sign of digoxin toxicity in infants. C. Restlessness: May occur due to hypoxia or discomfort but is not a specific sign of toxicity. D. Decreased respiratory rate: Not a hallmark sign of digoxin toxicity and may be more concerning for impending respiratory failure.