Research has explored the various reasons people participate in chemsex, along with the associated benefits and harms, including sexual risk behaviours, sexually transmitted and blood-borne infections (STBBIs) and mental health impacts. However, the specific relationship between chemsex and the risk of fatal overdose remains less well understood. This article summarizes key findings from a published perspective article1 looking at the evidence on the association between chemsex practices and overdose risks among gay, bisexual and other men who have sex with men (gbMSM). The perspective article also identifies critical knowledge gaps on this topic and outlines harm reduction interventions for service providers.
What is chemsex?
Chemsex (also referred to as party and play or PnP) refers to the use of psychoactive substances during sexual activities, primarily among gbMSM. The specific substances used, the sexual activities engaged in, and the reasons for participation can vary depending on the location, the context and the individuals involved. The reasons for participating in chemsex can include increasing feelings of intimacy or connection, libido, sexual arousal, confidence, disinhibition and/or stamina. While there is no consensus on the drugs used during chemsex, the authors highlight methamphetamine, gamma-hydroxybutyrate / gamma-butyrolactone (GHB/GBL) and synthetic cathinones as the substances people most often report using during chemsex.
What kind of research does the perspective article include?
The perspective article provides a synthesis of the current evidence on the risk of overdose among gbMSM who participate in chemsex.
What is the risk of overdose related to chemsex?
The perspective article suggests that there is a potential relationship between chemsex and overdose risks and that gbMSM may face unique and potentially elevated risks of overdose.
Data on the number of overdose events among gbMSM who participate in chemsex are lacking, primarily because of limited systematic documentation. Stigma may prevent men from disclosing involvement in chemsex, and healthcare providers may not consistently ask about these practices. In addition, forensic toxicology can only identify substances present at the time of death, meaning that determining whether chemsex was involved often relies on witness statements or other contextual evidence. As a result, there are currently no national data on overdose or toxicity deaths specifically among gbMSM engaged in chemsex.
However, the absence of surveillance data does not mean the absence of risk. Instead, a range of existing evidence can be used to show that overdose risk may be elevated in this context.
Research has demonstrated higher rates of unregulated substance use among gbMSM compared with non-gbMSM. Beyond the fact that gbMSM are more likely to use unregulated substances, almost a quarter of gbMSM globally are estimated to engage in sexualized substance use practices.
In Canada, higher rates of substance use among gbMSM are occurring within the context of an ongoing drug overdose crisis, where an ever-changing drug supply has heightened the risk of fatal outcomes. Since 2016, tens of thousands of people have died of substance toxicity across Canada. While there are no national data on overdose deaths specifically among gbMSM, evidence suggests that overdose deaths among men generally have been increasing. For example, in British Columbia, the rate of overdose deaths among men increased from 33.1 per 100 000 persons in 2016 to 70.3 in 2022.
Methamphetamine and GHB, drugs commonly used in chemsex, each carry their own particular and potentially fatal overdose risks. In Canada there were 3,479 apparent stimulant overdose deaths between 2018 and 2023, and in the United States, overdose deaths involving stimulants other than cocaine (primarily methamphetamine) increased by 180% between 2013 and 2019. GHB/GBL carries a notable overdose risk, as there is a narrow dosing window between intended effects and toxicity.
The recent rise in stimulants that unexpectedly contain fentanyl has introduced an additional risk of overdose to people who participate in chemsex and use methamphetamine. In 2018–19 the Health Canada Drug Analysis Service detected fentanyl or fentanyl analogues in up to 3% of stimulant samples nationally. In BC this figure reached 10%. The reported use of methamphetamine in chemsex, combined with the increased chance that stimulants unexpectedly contain fentanyl, establishes a potential drug overdose risk for gbMSM participating in chemsex. This is because individuals who participate in chemsex may face a heightened overdose risk from unknowingly consuming opioids, particularly if they do not have a high opioid tolerance. Repeated dosing can lead to small fentanyl exposures compounding and gradually increasing the overdose risk. Additionally, individuals may be less familiar with the effects of opioids and therefore less likely to quickly recognize and respond to opioid overdose, including giving naloxone.
Individual factors can increase the risk of overdose. An individual’s actions, such as dosing practices and frequency of use, intersect with their physiological factors, including their tolerance and underlying health conditions. Certain chemsex practices may further elevate overdose risk. For example, it is common for chemsex to involve repeated dosing over prolonged sessions which can increase risk of overdose if not properly monitored. Another practice that may heighten overdose risk is mixing multiple substances during a session. For example, combining GHB/GBL with other depressant drugs, such as alcohol or fentanyl, may sharply increase the risk of overdose.
What are the implications for service providers?
The perspective article highlights potential risks of overdose for gbMSM who participate in chemsex. These risks vary with individuals’ practices and knowledge. Service providers who work with gbMSM who participate in chemsex are well positioned to integrate harm reduction knowledge alongside STBBI prevention and other sexual health messaging. Such messaging could include safer substance use practices for different drugs (e.g., safer GHB dosing), education about the potential harms of mixing substances, and overdose identification and response. This could include recognizing what overdose looks like for different substances and how to give naloxone and to respond to different types of overdose. Service providers should consider traditional interventions such as providing safer drug use equipment, safer substance use education, and testing for HIV, hepatitis C and other STBBIs. Service providers should also be knowledgeable about health and substance use treatment initiatives led by the gbMSM community and psychosocial interventions appropriate for gbMSM participating in chemsex practices.
What is a perspective?
Perspectives are published journal articles meant to bring attention to emerging important information or topics. They may introduce a new hypothesis or provide alternate interpretations of existing work. Perspectives may bring attention to potential applications of new discoveries. Evidence used in perspectives varies; these articles typically involve a synthesis of available knowledge on a topic or question.2
References
- Duailibe F, Hull M, Montaner J, et al. Overdose risk in the context of chemsex among gay, bisexual, and other men who have sex with men. Harm Reduction Journal. 2026;23:50. Available from: https://doi.org/10.1186/s12954-026-01410-4
- Perspective submission guidelines. Harm Reduction Journal. Available from: https://link.springer.com/journal/12954/submission-guidelines/opinion
Production of this article has been made possible through a financial contribution from Health Canada's Substance Use and Addictions Program. The views expressed herein do not necessarily represent the views of Health Canada.
About the author(s)
Caleb Chepesiuk is CATIE's knowledge specialist, harm reduction programming. He has a master of arts degree in legal studies and previously worked in harm reduction service provision.