Buprenorphine initiation in fentanyl use: Practical strategies for family physicians.

OBJECTIVE: To provide family physicians with practical, evidence-informed guidance for initiating buprenorphine treatment in fentanyl use-including sublingual tablet, buccal film, and extended-release injectable formulations-and to outline structured approaches for transitioning patients from methadone to buprenorphine. SOURCES OF INFORMATION: The following were reviewed: Canadian and international clinical practice guidelines, randomized controlled trials, systematic reviews of buprenorphine formulations, cohort and emergency department studies of macro- and microinduction strategies, pharmacokinetic and withdrawal management studies in fentanyl-exposed populations, mortality and retention outcome analyses, and published methadone transition protocols. MAIN MESSAGE: In this time of widespread fentanyl use, buprenorphine initiation requires flexibility. Three practical oral induction pathways are available: standard induction (moderate opioid withdrawal confirmed), macroinduction (high-dose buprenorphine rapid stabilization), and microinduction (overlap buprenorphine while continuing full-agonist opioid). Extended-release injectable buprenorphine supports adherence and rapid test-dose initiation has the strongest evidence. Patients transitioning from methadone may use taper-and-switch, microinduction overlap, or slow-release oral morphine washout, selected according to methadone dose, destabilization risk, and patient preference. CONCLUSION: Family physicians can safely initiate and optimize buprenorphine treatment in community practice using structured but flexible approaches tailored to fentanyl exposure and patient goals. Clear protocols, anticipatory counselling, and early follow-up are central to successful treatment and retention in care.