In neonatal abstinence syndrome, onset of symptoms most commonly occurs

• A. At birth
• B. 24-72 hours after birth
• C. After 2 weeks
• D. After 1 month

Answer: (B)

The timing of withdrawal signs in NAS is tied to how quickly the opioid given to the mother clears from the newborn after birth. Once the baby is no longer receiving opioids from the placenta, withdrawal begins as the drug level in the infant falls. Because opioids vary in duration of action, most newborns show symptoms within about 24 to 72 hours after birth. Some short-acting opioids may appear a bit sooner (around 24–48 hours), while longer-acting ones can start closer to 3–4 days, but the common window is the first few days of life. So the most typical onset is 24–72 hours after birth.