Abstract
INTRODUCTION AND AIMS: North America is currently experiencing an epidemic of opioid overdose deaths, driven by the proliferation of fentanyl in the street drug market. Although buprenorphine/naloxone (BUP/NX) is an evidence-based, first-line opioid agonist for the management of opioid use disorder, a key challenge in its prescribing lies in the fact that it can precipitate opioid withdrawal during its initial induction process. At this time, there is minimal literature on the BUP/NX induction process in individuals who use illicit fentanyl regularly. DESIGN, METHODS AND RESULTS: A case series from a Vancouver, Canada addiction medicine clinic of three fentanyl-exposed patients who experienced unexpected, precipitated withdrawal when initiating BUP/NX. DISCUSSION AND CONCLUSION: These cases describe incidents of precipitated opioid withdrawal occurring after unusually long periods of fentanyl abstention. Although fentanyl is experienced as a short-acting opioid, the drug persists much longer in the body's peripheral tissues. Here, we highlight the new challenges fentanyl may pose to current BUP/NX induction strategies, and explore the possibility of a long-acting pharmacokinetic effect of fentanyl in the setting of repeated illicit use.