(brand names: Nucynta, Palexia, in India available as TAPAL by MSN Labs) is a centrally acting opioid analgesic with a dual mode of action as an agonist of the mu opioid receptor and as a norepinephrine reuptake inhibitor.
Its analgesic properties come into effect within thirty-two minutes of oral administration, and last for 4–6 hours.
It is similar to tramadol in its dual mechanism of action; namely, its ability to activate the mu opioid receptor and inhibit the reuptake of norepinephrine.
Unlike tramadol, it has only weak effects on the reuptake of serotonin, is a significantly more potent opioid and has no known active metabolites.
Its general potency is somewhere between that of tramadol and morphine, with an analgesic efficacy comparable to that of oxycodone despite a far lower incidence of side effects.
It was approved by the US FDA on the 26th of August 2011, by the MHRA of the UK on the 4th of February 2011 and by the TGA of Australia on the 24th of December 2010.
Systemic tapentadol resulted in dose-dependent decrease in right right central nucleus of the amygdala (CeA) neuronal activity only in neuropathy 1).
Has been found to be an effective medication for a wide variety of chronic pain conditions, including back pain, cancer-related pain 2). , and arthritic pain. It has also been found to have fewer gastrointestinal side effects than more traditional opioid-based therapies.
Tapentadol extended release was approved in 2012 for the treatment of Diabetic neuropathy (DN) 3). More recently, tapentadol extended release has been demonstrated to be effective in the management of painful diabetic neuropathy, an often debilitating condition affecting approximately one-third of all patients with diabetes 4) 5).
Twelve weeks of tapentadol in outpatients with moderate/severe chronic musculoskeletal pain showed satisfactory analgesic efficacy and tolerability, and had a positive influence on life quality and chronicity stage. The results are robust enough to warrant a subsequent study with a larger sample and a longer observation period 6).
A study compared the risk of receiving an opioid abuse diagnosis between tapentadol and oxycodone in 2 U.S. claims databases. The risk of receiving an abuse diagnosis was lower with tapentadol during the year of follow-up. Opioid prescribers and patients must be aware of the risk of abuse associated with all opioids 7).
There were 104 patients who met the inclusion criteria. Eighty patients were aged ≤6, 2-year-olds the most common age group (60.6%). There were 52 male and 52 female patients. Of the 104 patients, 93 had unintentional exposures. No deaths were reported. Sixty-two of the patients had no effect, 34 had minor effects, 6 had moderate and 2 had major effects. Thirty patients reported drowsiness and lethargy. Other effects reported included nausea, vomiting, miosis, tachycardia, respiratory depression, dizziness/vertigo, coma, dyspnea, pallor, vomiting, edema, hives/welts, slurred speech, pruritus, and hallucinations/delusions. Fifty-three patients were reported to have no medical intervention.
This is the first study examining the toxic effects of tapentadol in a pediatric population. Although a majority of the patients in this review developed no effect from their exposure, two had life-threatening events. The most common effects reported were opioidlike 8).