Study: THC+ Urine Samples Associated with Lower Opioid Concentrations In Pain Patients

St. Paul, MN: The presence of THC metabolites in the urine of patients undergoing pain management is associated with lower levels of opioids, according to data published in the journal Pain Management.

Investigators affiliated with MedTox Laboratories in Minnesota analyzed approximately 800,000 urine drug test results collected from pain management patients between the years 2016 and 2018.

Authors reported: "For each of the eight opioids monitored, lower mean concentrations were observed when THC-COOH [the primary metabolite of THC] was also present in the sample. The differences in opioid concentrations between the THC positive and THC negative groups were statistically significant … The largest shift was seen in codeine positive samples, followed by morphine, and fentanyl. … The buprenorphine positive group had the highest percentage of samples containing THC (20.8 percent), and hydrocodone had the lowest THC positive rate, 9.2 percent."

While researchers acknowledged that the findings were "consistent with data from self-report surveys of medical cannabis patients" in which subjects frequently report substituting cannabis for opioids, they cautioned that the observational design of the study precluded them from "assigning causation" to their results.

They concluded: "Further studies will hopefully elucidate if cannabis can or should play a role in pain management through the anti-nociceptive properties of THC and any potential interaction with opioids. From the perspective of opioid addiction treatment, it is interesting that the highest rate of THC use was seen in buprenorphine-positive samples as buprenorphine is frequently utilized as a component of medication assisted treatment for opioid dependency. Further studies are also needed to determine if THC/cannabis use alone or in combination with other medical treatments may help combat OUD (opioid use disorder)."

For more information, contact Paul Armentano, NORML Deputy Director. Full text of the study, "Reduced opioid levels from pain management patients associated with marijuana use," appears in Pain Management. Additional information is available from the NORML fact-sheet, "Relationship Between Marijuana and Opioids."