INTRODUCTION: Opioid use disorder is a chronic relapsing condition with major global public health impacts. Despite rising opioid use and overdose rates, data availability remains uneven, limiting understanding of treatment and harm reduction services worldwide. This study aims to provide a global overview of current practices in treatment and harm reduction for opioid use disorder.

METHODS: A global survey was conducted through the International Society of Addiction Medicine's Global Expert Network (ISAM-GEN) with participation from 42 addiction medicine societies/organizations representing 39 countries (15 from Europe, 14 from Asia/Oceania, 6 from the Americas, 4 from Africa). Between December 2022 and May 2023, participating organizations reported on opioid availability, treatment facilities, and harm reduction services in their countries.

RESULTS: Illicit prescription opioids were reported as the most commonly used opioids in over 87% of countries, followed by heroin (80%). Community-based outpatient settings were the most widely available treatment setting (92%), while shelters were the least common (28%). Methadone (75%) and buprenorphine (70%) were the most accessible agonist medications; morphine was reported by 11%, and 16% reported no access to these medications. Short-term medically managed inpatient withdrawal treatment was the most available program (74%). Longer-term treatment with methadone (69%), buprenorphine or buprenorphine-naloxone (64%), and naltrexone (59%) was also reported. Treatment in custodial settings was available in 68% of countries. Compared with the high availability of HIV antiretroviral therapy (95%) and testing (92%), harm reduction interventions were far less accessible: naloxone distribution (31%), safe consumption rooms (20%), and drug checking (15%). Fewer than 31% reported nationwide availability of 12-step programs.

CONCLUSIONS: This ISAM-GEN survey suggests major disparities in treatment and harm reduction for opioid use disorder. While some regions report broad access to evidence-based medications and psychosocial services, others lack important infrastructure. Harm reduction services, particularly naloxone distribution, supervised consumption sites, and drug checking remain limited. These findings suggest the need for stronger professional involvement in policy development and for data-driven, locally adaptable strategies to expand equitable access to comprehensive care worldwide.