Comparative Evaluation of Tramadol and Tapentadol on Psychomotor Function in Healthy Volunteers

Drugs affecting CNS are known to alter psychomotor function and cognition.(1) Centrally acting opioids analgesics are often used in clinical practice for relief of post operative pain , chronic cancer pain and traumatic pain. Opioids cause significant impairment of psychomotor or cognitive function and would hamper performing of complex daily activities. (2) Since newer centrally acting analgesics are now prescribed widely for variety of indications like nonmalignant, chronic low back pain or osteoarthritic knee pain and it becomes imperative that in addition to relieving pain, analgesic therapy must allow patients to maintain their independent and active state. Among these tramadol and tapentadol are commonly used analgesics.(3) Tramadol is a mu-opioid receptor agonist that also inhibits the reuptake of nor-epinephrine and serotonin. The non-medical use of prescription opioids, including tramadol, has increased in the U.S. over the last several years.(4) Oral tapentadol hydrochloride (HCl) is also a mu-opioid receptor agonist and monoamine-reuptake inhibitor approved by the Food and Drug Administration for treatment of moderate-to-severe acute pain in adults. Though tramadol is known to cause sedation but only a few studies are available in literature regarding their effects on psychomotor functions and cognition.(5) There is also a paucity of data on evaluation of tapentadol on psychomotor functions though a study has shown it not to interfere with driving ability.(6) To best of our knowledge no study has comparatively evaluated the effect of tapentadol and tramadol on psychomotor functions . Introduction Abstract Centrally acting opioid analgesics are frequently used in clinical practice and these drugs are known to cause sedation. To compare the effect of two commonly used analgesics tramadol and tapentadol on cricitical flicker fusion frequency (CFFF) which is the most sensitive indicator of cortical arousal.The study was conducted in ten healthy volunteers. It was a single dose, open label , cross over study. Volunteers were familiarized with critical flicker fusion test apparatus till they attained plateau level in their values. Volunteers were given 50 mg single dose of either of test drug orally and then crossed over with ten days wash out period between each trial .In each arm, volunteers were followed up to six hours.Both tramadol and tapentadol decreased the CFFF significantly during entire study period(p=0.000) from their respective pre-drug values. On comparison no statistical difference was observed between two drugs on CFFF (p>0.05). Result of current study highlights the impairment of psychomotor performance (CFFF) with both drugs in a similar manner . These observations could be of immense clinical importance especially when prescribed to ambulatory patients , more so while executing complex tasks.