The increase in benzodiazepine-laced drugs and related risks in Canada: The urgent need for effective and sustainable solutions

•Overdose rates in Canada continue to rise and are now primarily driven by illicitly manufactured fentanyl.•Policies to reduce risks have been ineffective and have led to unintended consequences including an unprecedented rise in adulterants in the illegal drug supply.•Most recently, the drug supply has become contaminated with synthetic benzodiazepine-laced opioids (i.e., 'benzodope') , which poses amplified risks for people who use drugs.•Effective and sustainable policies developed in partnership with people who use drugs must be implemented and evaluated to address this issue. The overdose crisis in Canada has continuously evolved and is increasingly challenging to contain, while efforts from governments and policymakers to address it have often fallen short and resulted in unintended consequences. One of the main repercussions has been an unprecedented rise in adulterants in the illegal drug supply, including a wide array of pharmacological and psychoactive compounds and chemicals, which has resulted in a progressively toxic drug supply. Most recently, there has been a stark increase in synthetic benzodiazepine-laced opioids (i.e., ‘benzodope’) in some Canadian jurisdictions. This unique combination carries distinct and amplified risks for people who use drugs including fatal and non-fatal overdoses, increased dependence and withdrawal symptoms, and places them in extremely vulnerable positions. The emergence of benzodiazepines within the illicit drug supply has substantially contributed to drug-related morbidity and mortality in Canada, and has further complicated current public health initiatives and overdose prevention efforts. This reality underscores the need for effective and sustainable policy solutions to address the evolving overdose epidemic including increased knowledge and education on the specific harms of opioid and benzodiazepine co-use (especially in regards to the complexity of opioid/benzodiazepine overdoses), scaling-up harm reduction measures, and eliminating the toxic drug supply altogether.