Rapid Methadone Induction in a General Hospital Setting: A Retrospective, Observational Analysis.

BACKGROUND: Outpatient methadone guidelines recommend starting at a low dose and titrating slowly. As fentanyl prevalence and opioid-related mortality increases, there is a need for individuals to rapidly achieve a therapeutic methadone dose. Hospitalization offers a monitored setting for methadone initiation, however dosing practices and safety are not well described. METHODS: Retrospective, observational analysis of hospitalized patients with opioid use disorder seen by an inpatient addiction consult team in an academic medical center who were newly initiated on methadone between 2016 and 2022. We calculated initial daily dose, maximum daily dose, timing interval of dose escalation, whether patients were connected to an opioid treatment program (OTP) prior to discharge, whether adverse effects or safety events occurred during the hospitalization, and whether such events were definitely or probably related versus possibly related or unrelated to methadone. RESULTS: One hundred twelve patients were included. The mean initial daily methadone dose administered was 32 mg (range: 10-90 mg). The mean maximum dose reached was 76.8 mg (range 30-165 mg). The mean number of days from initial to peak dose was 5.6 days (range 1-19 days). Overall, 30% of patients experienced a safety event, most commonly sedation. Only 4 safety events were deemed probably or definitely related to methadone. In regression analyses, there was no significant difference between starting doses among patients with or without sedation but there was a relationship between last dose and the likelihood of any possibly related event, with those ending at a dose of 100 mg or higher having a higher likelihood event, compared to those ending at lower doses (47.8% vs 12.4%, P < .001). Seventy-six percent were connected to OTP before discharge. CONCLUSION: Among hospitalized patients initiating methadone, rapid dose titration was infrequently associated with related safety events and most were connected to community-based methadone treatment before discharge.