Communicating risk in the context of methadone formulation changes: A qualitative study of overdose warning posters in Vancouver, Canada.

Background: British Columbia, Canada’s provincial methadone program recently replaced their existing methadone formulation with a formulation ten times more concentrated. The transition raised concerns about heightened risk of accidental overdose, leading two organizations to disseminate methadone overdose warning posters during the transitional period. This study explores people who use drugs’ (PWUD) perceptions of these warning posters.

Methods: Qualitative interviews were conducted with thirty-four PWUD enrolled in methadone maintenance treatment in Vancouver. Participants were recruited from ongoing cohort studies of drug-using individuals. Interview transcripts were analyzed thematically, focusing on participants’ perceptions of the warning posters and potential impacts on drug-related risks.

Results: Overdose warning posters constituted a key source of information about the methadone formulation change, but did not provide adequate information for all participants. Participants articulated a preference for descriptive language, focusing on changes in concentration rather than “strength”, and universal hazard symbols to effectively communicate overdose risks.

Conclusion: Participants indicated that warnings employing descriptive language more effectively communicated risk of methadone overdose. Future overdose warnings for drug-using populations must provide adequate information for the intended audience, and be communicated to PWUD through multiple channels.