Dr. Mark Lysyshyn is a medical health officer with Vancouver Coastal Health in British Columbia, Canada. The Vancouver region, like many parts of North America, has been strongly affected by the rise in opioid-related fatalities. Dr. Lysyshyn is among those working to reduce fatalities by researching and expanding harm reduction tools.
He recently co-authored a study looking at drug checking for fentanyl at Insite, a supervised consumption facility. It found a very high prevalence of fentanyl in heroin samples and also showed users do change their behavior, primarily by reducing their dose, when they know their drugs contain fentanyl. This suggests expanding the availability of drug checking could give users actionable information that will reduce overdoses.
You can find the study here: https://harmreductionjournal.biomedcentral.com/articles/10.1186/s12954-018-0252-8