Is it possible for withdrawal signs in NAS to be delayed beyond 7 days of age?

• A. Yes
• B. No
• C. Only for heroin
• D. Only for methadone

Answer: (A)

The timing of NAS symptoms depends on the opioid the mother used and how long the drug stays in the infant’s system. Methadone has a longer half-life than heroin, so the neonate clears it more slowly. Because of this extended clearance, withdrawal signs can emerge later, sometimes after 7 days or even later. So it is possible for NAS symptoms to be delayed beyond a week after birth, especially with methadone exposure or other long-acting opioids, and sometimes with poly-substance exposure or breast milk exposure as well. This is why clinicians stay vigilant for signs of withdrawal beyond the immediate first week, particularly in infants whose mothers were maintained on methadone.