Children with altered mental status show a change in personality, behavior, or responsiveness. They may appear somnolent, difficult to rouse, or completely unresponsive. This can be life-threatening if it is not recognized and treated promptly. It often results in hypotonia, which may lead to airway obstruction and interfere with respiration, resulting in hypoxemia and eventual respiratory failure.

Infants and young children may present with altered mental status from causes including hypoxemia, shock, seizures, sepsis, meningitis, hyperthermia, hypothermia, and hypoglycemia. The focus here is on hypoglycemia as a common cause that requires immediate treatment. Transient hyperinsulinemic neonatal hypoglycemia is seen in neonates of diabetic or pre-eclamptic mothers, premature infants, small-for-gestational age infants, or infants with fetal distress. Infants of mothers taking hypoglycemia-inducing drugs may be predisposed to hypoglycemic conditions. There are cases of persistent hyperinsulinism in infants that may be due to familial and nonfamilial hyperinsulinism, beta-cell adenoma (insulinoma), or beta-cell hyperplasia. Other causes of newborn hypoglycemia include endocrine deficiencies and congenital inborn errors of metabolism.