American consumers are responsible for the consumption of 80% of the global painkiller supply each year, and many of these drugs are abused and are not used by the person the medication was prescribed for or for the intended purpose of the prescription. Researchers at the University of Kentucky investigated whether Tramadol, a popular prescription pain medication prescribed widely across the country, was habit forming. The study results will be included in the next edition of the journal Psychopharmacology.

The lead author of the study was William W. Stoops, Ph.D. According to Dr. Stoops “Prescription pain pill abuse is a real problem in Kentucky. We have lots of overdoses. We held a summit here in February specifically about partnering law enforcement and medicine to tackle this problem.” The study involved Naltrexone, which blocks opoid receptors in the brain. Dr. Stoops explained “When we’ve given them placebo and the opioid receptors are not blocked, tramadol and hydromorphone produce fairly similar effects. They make subjects say that they’re high, they make subjects say that they like the drug, those kind of things. Tramadol does produce some bad effects; folks are saying that it makes them a little nauseous so it is a little distinct from hydromorphone in that manner, which is important.”

Dr. Stoop continued with “When we gave folks naltrexone and blocked the opioid receptors, hydromorphone didn’t produce any effects, it was like we’d given them placebo. It completely blocked the effects of hydromorphone because the primary way hydromorphone works is on the opioid receptors in the brain; they’re blocked so of course hydoromorphone isn’t going to produce an effect. With tramadol, we did not see anywhere near the blockaded effect that we saw with hydromorphone. We need to test a higher naltrexone dose to confirm that this is the case.”