• Uses prescription opioids for chronic pain, especially at high doses
• Uses opioids in combination with other sedating substances (like benzodiazepines or alcohol)
• Uses opioids and have certain medical conditions such as HIV, liver disease, lung disease, or depression
• Injects opioids 
• Has Access to opioids (including prescription opioids)
• Has an opioid dependence, particularly following reduced tolerance
• Has prior history of opioid overdose

Source: Narcan® Caregiver brochure, https://www.narcan.com/wp-content/uploads/2021/12/Caregiver_Brochure.pdf