Use of a novel prescribing approach for the treatment of opioid use disorder: Buprenorphine/naloxone micro-dosing - a case series

Introduction and Aims Buprenorphine/naloxone is an evidence-based treatment for opioid use disorder, but an identified limitation is the period of required opioid abstinence prior to induction on the medication. 'Micro-dosing', or using incrementally increasing doses of buprenorphine/naloxone over time, may be a way to overcome this challenge as it can be done in parallel with the ongoing use of other opioids (either illicit or prescribed). Design and Methods A retrospective case series (January to December 2018) was completed of seven participants who underwent buprenorphine/naloxone induction using micro-dosing at two outpatient addiction clinics in Vancouver, Canada. Results Seven participants completed a 7-day buprenorphine/naloxone micro-dosing protocol. Prior to and during the induction, one participant was prescribed methadone, three were prescribed slow release oral morphine and three used only illicit fentanyl. Participants were prescribed sublingual buprenorphine/naloxone: 0.5 mg once daily (day 1), 0.5 mg twice daily (BID; day 2), 1 mg BID (day 3), 2 mg BID (day 4), 3 mg BID (day 5), 4 mg BID (day 6) and 12 mg once daily (day 7). On day 7, all prescribed or illicit full opioid agonists were discontinued. Buprenorphine/naloxone was subsequently titrated to a daily dose of between 12 and 32 mg. All patients reported success with buprenorphine/naloxone induction with no precipitated withdrawal. Discussion and Conclusions Buprenorphine/naloxone micro-dosing may offer a promising alternative approach for successful induction for individuals with opioid use disorder who desire treatment with buprenorphine/naloxone, and further research to determine effectiveness is warranted.