Skip to main content
PAINWeek 2025 Main banner
Icon Legend
This session is not in your agenda.
This session is in your agenda. Click to remove it

Urine Drug Test Results from Patients with Chronic Pain Receiving Partial Agonist Versus Full Agonist Opioid Therapy

P-022 - (Poster #22) Urine Drug Test Results from Patients with Chronic Pain Receiving Partial Agonist Versus Full Agonist Opioid Therapy

Thursday, September 4, 2025
4:00 PM - 5:30 PM PST
Location:  Exhibit Hall (Level 4)
Background: The use of buprenorphine (a partial μ-opioid agonist with buccal film and transdermal patch formulations approved for severe and persistent pain) has been addressed in recent pain management guidelines. The 2022 updated CDC Guideline for Prescribing Opioids for Chronic Pain included a recommendation to consider buprenorphine for tapering patients who have continued to use high doses of opioids without seeing benefits, who have been unable to taper, and who do not meet the criteria for OUD1. Another 2022 guideline from the US Department of Veteran Affairs and Defense on the use of opioids for chronic pain recommended consideration of buprenorphine instead of full agonist opioids (FAO) for patients prescribed daily opioids2. Buprenorphine has high binding affinity at μ-opioid receptors, yielding potent analgesia, a ceiling effect on respiratory depression and euphoria, and lower likelihood of other adverse events commonly observed with conventional opioid use3-5. Considering the pharmacology of buprenorphine, it may be possible that those prescribed buprenorphine rather than FAO are less likely to engage in illicit drug use. Few studies have utilized real-world data to investigate differences in concomitant illicit drug use in patients with chronic pain prescribed buprenorphine compared to those prescribed FAO.

Purpose/Objectives: The purpose of this study was to first characterize patients managed by a pain clinic that were prescribed (1) buprenorphine buccal film (BBF), (2) buprenorphine transdermal patch (BTP), or (3) FAO therapy (including hydrocodone, hydromorphone, morphine, oxycodone, and oxymorphone) and second, evaluate the presence of illicit drugs (heroin, fentanyl, cocaine, and methamphetamine) in their urine drug tests (UDT).

Methods: UDT results from people with chronic pain treated in pain clinics were extracted from the Millennium Health (MH) database. MH is a large specialty laboratory that processes urine and oral fluid specimens from all US states across multiple clinical specialties. The dataset included specimens tested January 2019-March 2025. Along with the specimen, the ordering physician provided the medications prescribed to the patient at the time of specimen collection. The specimens analyzed were limited to those that listed a prescribed medication in only one of the study groups (mutually exclusive at specimen level) however patients could have multiple UDTs and could have had different prescribed medications over time, hence unique individuals could have specimen level results in more than one study group. Frequencies of demographics (sex, age, payor group) were estimated for each study group. Pearson chi-square tests for categorical data and independent sample t-tests for continuous data were calculated to compare unique patients between groups. History of any substance use disorder (SUD) diagnoses (and opioid use disorder (OUD) diagnoses as a subset), and the presence of illicit drugs (heroin, fentanyl, cocaine, and methamphetamine) in UDT specimens were also compared across study groups using Pearson chi-square tests (p< 0.05 significance level).

Results: A total of 144,399 specimens from 35,941 unique patients and 1,022 unique providers were evaluated. BBF group had 3,675 unique patients and 9,363 specimens (average 2.55 (SD 2.83) specimens per patient); BTP group had 5,299 unique patients and 12,235 specimens (average 2.31 (SD 2.42) specimens per patient); FAO group had 26,607 unique patients and 115,606 specimens (average 4.34 (SD 4.07) specimens per patient). Females represented a majority in all study groups, though BBF (62.2%) and BTP (64.3%) patients were more likely to be female compared to FAO (59.0%) patients. BBF patients had the lowest mean age (56.1 years, SD 12.8) and FAO patients had the highest mean age (59.4 years, SD 12.2). BBF patients had the highest percentage of commercial insurance coverage (24.9%) compared to BTP (18.5%) and FAO (17.4%). Conversely, BBF patients had the lowest percentage with Medicare/Medicaid coverage (51.7% compared to 61.4% of BBF and 57.4% of FAO). A significantly higher rate of SUD, and specifically OUD, was reported in the BBF (10.7% SUD, 8.6% OUD) and BTP (15.0% SUD, 11.3% OUD) groups compared to the FAO (8.2% SUD, 6.4% OUD) group. Despite this difference, the percent of specimens that tested positive for heroin were statistically significantly lower for the BBF (0.0%, n=1 out of 8,342 specimens tested) patients than the BTP (0.1%, n=8 out of 10,826 specimens tested) patients (p=0.045) and the percentage of specimens that tested positive for fentanyl were statistically significantly lower for the BBF (0.5%, n=45 out of 8,674 specimens tested) patients than the FAO (0.9%, n=950 out of 106,262 specimens tested) patients (p=0.0003) and for the BTP (0.6%, n=61 out of 11,089 specimens tested) patients than the FAO (0.9%, n=950 out of 106,262 specimens tested) patients (p=0.0002). The presence of cocaine was also statistically significantly lower for the BBF (0.4%, n=36 out of 8,485) patients than the BTP (0.7%, n=72 out of 11,031 specimens tested) patients (p=0.033) but no different between BBF and FAO. There was no difference in the presence of methamphetamine between BBF and the comparator groups.

Conclusions/Implications for future research and/or clinical care:

This study evaluated patient profiles and UDT results in patients managed by pain clinics based upon their prescribed pain medications (BBF, BTP or FAO). BBF and BTP patients were more likely to have a history of SUD and OUD which was not unexpected based upon common prescribing practices and the recommendations of buprenorphine for pain in the OUD population. Consistent with previously published data6, the overall presence of illicit drugs in UDTs of patients managed by pain clinics was low (< 1%). With differential prescribing, one would expect detection of illicit drugs to potentially be higher in patients treated with buprenorphine than in patients receiving FAO. However, these data suggest that the rate of detection of heroin and fentanyl were similar or lower in the BBF group. The detection of cocaine was also similar or lower in the BBF group compared to other study groups. There were no differences in the rate of methamphetamine detection. These data support previous findings of overall low illicit drug detection in patients managed in pain clinics as well as reduced risk with partial µ-opioid agonist for pain therapy in the appropriate patient populations, which in this instance includes those with a history of SUD/OUD.