Maintaining Evidence-based Opioid Agonist Treatment During a Methadone to Buprenorphine Rotation With Slow-release Oral Morphine

Patients may transition from methadone to buprenorphine-naloxone for various reasons. Alternative methods to ease this transition have been reported in the literature including low-dose buprenorphine (microdosing) and using slow-release oral morphine (SROM). We present the case of a 34-year-old male presenting to the hospital with stimulant-induced psychosis, wishing to transition from methadone to buprenorphine. Given the long and variable half-life of methadone, a wash-out period of at least 5 days is recommended to avoid precipitated withdrawal, before starting buprenorphine-naloxone. This can be a high-risk period if a patient decided to leave against medical advice during the transition. To reduce withdrawal symptoms during this period and to maintain the patient on opioid agonist treatment, SROM was started the day after methadone was discontinued. SROM and immediate-release morphine PRN were increased every 1-2 days (maximum dose of 570 mg daily) and on day 6, a rapid induction of buprenorphine-naloxone was initiated. In 3 days, he stabilized on 32 mg and continued on this dose for the remainder of his hospitalization. He later transitioned to buprenorphine extended-release injection. This case highlights an approach to facilitate transitioning from methadone to buprenorphine-naloxone and subsequently buprenorphine extended-release injection that prioritizes patient comfort and treatment retention, maintaining the use of evidence-based opioid agonist therapy throughout treatment.