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

- Posters used to alert people to methadone formulation change in Vancouver, Canada.
- Study explores people who use drugs' (PWUD) views of two warning posters.
- Warnings of “stronger” methadone were perceived to increase drug-related risks.
- Descriptive language and universal hazard symbols more effectively conveyed risk.
- Posters and other PWUD were key sources of information about formulation change.