Naloxone is an opioid overdose antidote that has been used safely for over 40 years. The large majority of PWID respondents had heard about naloxone, the opioid overdose antidote Almost all participants reported naloxone functions correctly A substantial minority of the entire sample reported knowing about take home naloxone programs, and this knowledge: Increased over time; but Varied by jurisdiction, with knowledge highest in jurisdictions with current programs Reports of having received training in naloxone administration increased over time as did the relatively rare but increasing reports of naloxone administration after having been trained