Analgesia, anesthesia (narcotic analgesic)
Neonates, infants, and children < 12 yr: 5–15 μg/kg IV injected over 3–5 min or 0.5–3 μg/kg/min continuous infusion (limited experience and doses poorly established).
Adults: IV continuous infusion 0.5–1.5 μg/kg/min.