This lecture on recreational drug use by Marta Boffito from London was a nice summary of some of the trends they are seeing in the UK and how this may affect treatment.
Marta started by highlighting a paper from 2014 - the ASTRA study which identified significant polydrug use (of recreational drugs) amongst MSM in the UK and its association with condomless sex. Whilst this may be a risk for HIV transmissions, the potential interactions with antiretrovirals in people living with HIV should also be considered. The Liverpool website neatly summarises some of these interactions here.
Of particular concern is the use of GHB or GBL (collectively known as ‘G’) as a party drug. This synthetic version of an endogenous hormone is rapidly absorbed and has a relatively short half life, leading to people sometimes taking multiple doses to maintain their ‘high’. The main concern with it is the fact that it has a narrow therapeutic range, and doses up to 3ml can cause death. In addition, ethanol interferes with the metabolism, as do ARVs such as PIs and cobicistat. Whilst crystal meth seems to be getting much attention at the moment (and something I see in my clinical practice in central Sydney frequently), the use of ‘G’ is of significant concern, particularly in patients with these potential drug-drug interactions. When reviewing or commencing PIs or pharmaco-enhancers such as cobicistat, it is crucial to take a full drug history and warn patients about potential interactions, even if they do not freely admit to using such drugs.