What is a typical manifestation of neonatal abstinence syndrome in a newborn from a mother who used methadone during pregnancy?

Neonatal abstinence syndrome (NAS) is a collection of symptoms that occur in newborns who were exposed to certain substances in utero, including opioids like methadone. A hallmark sign of NAS is excessive crying, particularly characterized by a high-pitched tone. This excessive high-pitched cry reflects the infant's irritability and central nervous system hyperactivity, which are typical manifestations of withdrawal due to maternal substance use.

In contrast, hyporeactivity might suggest lethargy or decreased responsiveness, which is not a common feature of NAS induced by opioid exposure. Acrocyanosis may occur in newborns but is generally associated with other conditions, such as immature circulatory systems, rather than specifically indicative of NAS. Similarly, while a respiratory rate of 50 breaths per minute is a normal range for a neonate, it does not specifically indicate NAS and can fall within normal respiratory patterns seen in newborns.

Thus, the excessive high-pitched cry effectively reflects the irritability and neurological overstimulation that are commonly seen in infants experiencing withdrawal from substances like methadone.