This study sought to understand the personal and social context of chemsex and the nature of harm reduction need. Use of these drugs by gay men in London appears to have risen sharply from relatively low levels and, as yet, there is little data to inform appropriate harm reduction services. Chemsex is a colloquial term used by gay men in some parts of the UK to describe the use of psychoactive substances (typically mephedrone, GHB/GBL or crystal methamphetamine) during sex.
