Differential classification for alkyl nitrites: a regulatory solution to minimize harms and maximize benefits?

Poppers (alkyl nitrites) produce a headrush and relax smooth muscle when inhaled. As such, poppers are often used to facilitate comfortable and pleasurable sex among gay, bisexual, and queer men as well as trans and non-binary people. While policy measures to control access to poppers vary across international jurisdictions (ranging from criminalization to prescription or grey market access), limited evidence is available to inform effective health and regulatory policy. Differential classification (i.e., enacting varied regulatory measures, controlling poppers formulations differently according to their risk profiles) has recently been established in Australia as a means to reduce harms. Despite a lack of consensus among regulators with respect to differential classification as a public health strategy for poppers use, the possibilities to reduce harm may be far greater than currently recognized. Through this essay, we examine the evidence behind differential classification of alkyl nitrites, with an eye to improving policy and informing research across jurisdictions. Drawing on research from the 1890s to present day, we argue that current discourse has not appropriately captured data available to elucidate and disentangle health outcomes across different alkyl nitrite formulations; yet, underutilized data suggest important reductions to risk that may be possible through differential classification. Promising findings from archival research include diminished propensity for overdose (via methemoglobinemia) observed in octyl and tert-butyl nitrite, which may provide an avenue to reduce poppers-related deaths, and variation in physiological outcomes across the alkyl nitrites which may help to explain anecdotal reports of variation in health outcomes such as headache.