In people with opioid use disorder receiving opioid agonist treatment (methadone or buprenorphine), does concurrent use of other substances increase the risk of overdose?

High-quality evidence shows that concurrent use of benzodiazepines and other CNS depressants with opioid agonist treatments significantly increases the risk of overdose. Monitoring and mitigative strategies such as naloxone co-prescription are advised to manage this risk.