Addressing injecting related risks among people who inject both opioids and stimulants: Findings from an Australian survey of people who inject drugs

Background: Opioids and stimulants are the most commonly injected illicit drugs worldwide and in Australia. While some people who inject drugs (PWID) prefer either opioids or stimulants, others regularly use both opioids and stimulants. Limited available research indicates that those who use opioids and stimulants together, either in combination or alternating between the two, may engage in injection-related practices which potentially place them at greater health risk and could lead to poorer health outcomes. Methods: Participants were recruited nationally through member organizations of the Australian Injecting and Illicit Drug Users League (AIVL); these organizations represent PWID in each Australian state and territory. This study compared a sample of PWID (N = 535) who reported past-month injection of opioids only (N = 173), stimulants only (N = 208), or both (N = 154) on a range of health and wellbeing outcomes. PWID completed a survey assessing drugs injected, frequency of injecting, receptive equipment sharing, psychological distress, selfreported hepatitis C (HCV) status, experienced and internalized stigma, drug use salience, and community attachment. Results: People who injected both opioids and stimulants reported more frequent injecting, more experiences of stigma, and greater reported HCV diagnosis than people who injected stimulants or opioids alone. They also showed greater attachment to a community of PWID and greater salience of drug use to their identity. Conclusions: The findings of increased injecting and broader harms associated with injecting both stimulants and opioids are important for tailoring harm reduction and intervention designs for people who use both opioid and stimulant drugs, including prioritizing peer-based approaches.