"It's like scratching at the door": Experiences of outpatient buprenorphine low dose initiation among people using fentanyl.

BACKGROUND

The fentanyl-driven overdose crisis has heightened challenges in buprenorphine initiation, as traditional methods risk precipitated withdrawal due to fentanyl's prolonged presence in the body. Buprenorphine low-dose initiation (LDI) offers a gradual approach to starting buprenorphine but requires continued full-agonist opioid use in outpatient settings, where success rates remain low and patient experiences have not been evaluated.

OBJECTIVES

To identify barriers and facilitators to successful LDI completion and inform strategies to improve outpatient buprenorphine treatment.

METHODS

We conducted 19 semi-structured interviews with people with opioid use disorder using fentanyl who had attempted LDI in the past three months. Using the COM-B framework, we applied thematic analysis to identify barriers and facilitators to LDI completion from interviews until reaching thematic saturation.

RESULTS

We found that barriers and facilitators to LDI completion were linked to five COM-B model components: physical capability, physical opportunity, social opportunity, reflective motivation, and automatic motivation. Despite high desirability and acceptability among participants towards starting LDI, several main barriers to LDI completion emerged, including difficulty tolerating "waves" of discomfort throughout LDI, anticipatory anxiety of precipitated withdrawal with each buprenorphine dose, lack of symptomatic response from small buprenorphine doses, loss of "high" from fentanyl, readily available fentanyl access leading to temptations to use, unstable or triggering housing environments, and being around others using fentanyl. Facilitators for completing LDI included increased optimism for success, the appeal of gradual recovery, bubble-packing medications, use of prescribed and non-prescribed drugs, supportive personal relationships, and non-stigmatizing clinic and pharmacy environments.

CONCLUSIONS

Our study applied a novel behavior-change framework to understanding barriers and facilitators to LDI completion. Barriers aligned closely with the COM-B model, providing a foundation for developing future interventions to enhance buprenorphine uptake and acceptability among people with OUD using fentanyl. Addressing barriers to automatic motivation is likely to have the largest benefit, with interventions such as incentivization (e.g., gift cards for completing LDI), environmental restructuring (e.g., temporary housing or comfort spaces for LDI), behavior modeling (e.g., peer coaches), and enablement (e.g., 24/7 phone lines for patients to call) most directly addressing this barrier category.