Chemsex is a term used by gay or bisexual men to describe sex that occurs under the influence of drugs.
With the exception of ketamine these are all stimulant drugs which means that they increase heart rate and blood pressure and trigger feelings of euphoria. Crystal methamphetamine, GHB/GBL and mephedrone are also reported to facilitate feelings of sexual arousal.
There is some concern that the use of crystal meth, GHB/GBL and mephedrone may be raising the risk that STIs and HIV could be transmitted.
A full exploration of the role, nature and risks of Chemsex in South London can be downloaded here
Updated December 2016