Neonatal Opioid Withdrawal Scoring

Neonatal opioid withdrawal syndrome (NOWS), historically called neonatal abstinence syndrome (NAS), develops when a newborn accustomed to chronic opioid exposure in utero is separated from that exposure at birth. While the fetus is exposed, opioid stimulation alters mu-opioid receptor signalling and the balance of central noradrenergic activity. After cord clamping, that opioid effect stops abruptly; the resulting unopposed autonomic and central nervous system activity produces withdrawal. The pattern is broader than tremors alone. Neurologic findings may include a high-pitched cry, irritability, increased tone, tremors, poor sleep, and, in severe cases, seizures. Gastrointestinal dysfunction appears as disorganised or ineffective feeding, vomiting, loose stools, and poor weight gain. Autonomic activation can cause sweating, sneezing, temperature elevation, tachypnea, and mottling. The score or function assessment describes severity; it does not establish the diagnosis by itself. Withdrawal signs overlap with hypoglycemia, hypocalcemia, sepsis, respiratory disease, medication effects, and neurologic injury. The infant’s exposure history, examination, feeding and sleep pattern, vital signs, weight trend, and response to supportive care must be interpreted together.