Outpatient Low-dose Buprenorphine Initiation for Opioid Use Disorder Should Be Offered, but Has Low Rates of Treatment Completion and Retention

In contrast with traditional or high-dose buprenorphine initiation protocols, low-dose buprenorphine initiation (LDI) protocols circumvent the need for opioid abstinence while also minimizing precipitation of opioid withdrawal. Most reports describing LDI among people with non-prescribed fentanyl use occurred in the hospital setting. This retrospective cohort study of people with daily non-prescribed fentanyl use evaluated associated outcomes with a four-day and a seven-day LDI in the outpatient setting.

• Overall, 126 individuals attempted LDI of buprenorphine 175 times.
• LDI was successfully completed in 60 attempts (34 percent); of these, 39 attempts (22 percent) resulted in buprenorphine retention at 28 days.
• Logistic regression analyses found no significant differences between the four-day and seven-day LDI protocols and successful buprenorphine initiation.
• In adjusted analyses, lower odds of successful LDI completion were associated with: repeated LDI attempts (second LDI attempt: adjusted odds ratio [aOR], 0.3; three or more LDI attempts: aOR, 0.22), and unstable housing (transitional housing: aOR, 0.3; being unhoused: aOR, 0.4).

Comments: This study highlights the challenges of outpatient buprenorphine LDI, including low rates of treatment completion and retention, especially among people without stable housing. There was a non-significant  trend towards higher treatment completion with the four-day protocol, indicating a possible direction for future study. People with two or more unsuccessful LDI attempts may better tolerate a traditional buprenorphine initiation at home with supportive medications, a high-dose buprenorphine initiation in clinic with supportive medications, or a direct initiation of injectable buprenorphine. Alternatively, a patient may prefer to transition to methadone when available.

Susan Calcaterra, MD, MPH, MS

Reference: Suen LW, Chiang AY, Jones BLH, et al. Outpatient low-dose initiation of buprenorphine for people using fentanyl. JAMA Netw Open. 2025;8(1):e2456253.