Morphine-3-glucuronide
from morphine
What it isMorphine-3-glucuronide, the major morphine metabolite, with no analgesic activity.
Why it mattersIt is neuroexcitatory: accumulation is implicated in hyperalgesia, allodynia, and myoclonus during high-dose or renally impaired morphine therapy.
What it changesBecause it is renally cleared, kidney failure turns steady morphine dosing into progressive M3G load — a reason to rotate opioids.
NO BOXED WARNINGS