Scientific evidence accumulated over the years confirms that breast milk has many advantages over formula feeding.1.2 The difficulty of monitoring an infant's intake from breast-feeding may occasionally lead to problems in the rare baby in whom inadequate intake of food and fluids is not apparent. In the present case, a 2-week-old infant developed severe hypernatremic dehydration. Hypernatremia has not been reported previously in a totally breast-fed infant. CASE REPORT A 3,860-gm white female infant was born to a 28-year-old primigravida mother at 40 weeks' gestation after an uncomplicated prenatal course. The amniotic fluid was meconium stained, and cardiac decelerations were noted during oxytocm induction.