What finding indicates a newborn is experiencing withdrawal if the mother was taking methadone during pregnancy?

In the context of a newborn experiencing withdrawal due to maternal methadone use during pregnancy, hypertonicity is a significant finding. Hypertonicity in newborns refers to increased muscle tone, which can manifest as rigidity or stiffness of the limbs. This is an important indicator because neonates exposed to opioids in utero, such as methadone, often exhibit symptoms consistent with withdrawal, including increased muscle tone along with other signs.

Neonatal withdrawal syndrome typically presents with a range of symptoms due to the effects of opioids on the developing nervous system, which can lead to alterations in usual muscle tone. Hypertonicity is particularly notable as it demonstrates the central nervous system's overactivity response to the absence of the drug after delivery. This increased tone can be associated with other withdrawal signs such as irritability, tremors, and feeding difficulties.

Although excessive crying and poor feeding are also symptoms that may be seen in newborns withdrawing from substances, hypertonicity is more specifically characteristic of the neuromuscular changes seen in this scenario, making it a key indicator of withdrawal from methadone.