What Is Tapentadol ?
Tapentadol is the first representative of a new class of centrally acting analgesics called MOR-NRI. It is an opioid receptor μ (MOR) agonist and a norepinephrine reuptake inhibitor (NRI). Unlike tramadol, it does not have a significant effect on serotonin reuptake. Despite as much as 50 times lower affinity for the opioid receptor μ (MOR) compared to morphine, in experimental studies tapentadol administered intravenously has only 2-3 times weaker effects than morphine. Such a strong analgesic effect of tapentadol despite the relatively weak affinity for the opioid receptor μ (MOR) is the result of the synergism of its two mechanisms of action, i.e. the impact on the opioid receptor μ (MOR) and the descending noradrenergic antinociceptive system. It is believed that the agonistic effect of tapentadol in relation to the opioid receptor μ (MOR) is responsible for relieving nociceptive pain, while the noradrenergic mechanism of action is responsible for its effectiveness in relieving various forms of neuropathic pain.