Centrally acting oral analgesic with opioid and nonopioid activity.
Thought to act via mu-opioid agonist activity and the inhibition of norepinephrine reuptake.
Mu-opioid agonist inhibits transmission of pain impulses through binding to mu-opioid receptors via ascending pathways.
Norepinephrine reuptake inhibitor enhances the inhibition of pain signaling through norepinephrine reuptake inhibition via descending pathways.
Does not affect P450 enzymes.
Dosing one 50 mg or 100 mg tablet every 4-6 hours.
Maximum dose 600 mg/day.
Has 18 times lesser affinity than morphine and blocks reuptake of neuroepinephrine with no effect on serotonin.
Affects intraneuronal norepinephrine levels, and is useful in the pain that involves shooting or burning pain is consistent with neuropathies and radicular symptoms: post herpetic neuralgia, diabetic neuropathy and chronic low back pain with radiculopathy.