Should be avoided in patients with renal and hepatic disease.
Is primarily metabolized via glucuronization phase II enzymes and avoids CYP Phase I metabolism into active and in active metabolites.)
An active metabolite, morphine-6-glucuronide, contributes to pain control and can increase toxicity as it accumulates with renal insufficiency.
Morphine-3-glucuronide, a non-active metabolic agent, can produce neurotoxicity.
Morphine-3-glucuronide and morphine-6-glucuronide accumulation can lead to confusion, sedation and myoclonus.
Half-life of 4 hours.
Has a 3:1 oral to parenteral potency ratio.
Peak analgesic effect around one hour to an hour and a half after administration.
Among patients with COPD and severe chronic restlessness, daily low-dose extended release morphine does not significantly reduce the intensity of worst breath assist after one week of treatment.