May 26, 2016

expert reaction to study on cannabis vaping using e-cigarettes

Cannabis is a class B drug in the UK but is in use for therapeutic purposes in a number of countries for various diseases, and a paper published in the journal Scientific Reports has reported that e-cigarette devices could be effective in administering therapeutic doses of the drug.

Dr Michael Bloomfield, Clinical Lecturer in Psychiatry, MRC Clinical Sciences Centre, UCL, said:

“This paper describes the use of electronic cigarettes to consume cannabis. There is concern by some scientists that whilst the practice of using butane hash oil (‘BHO’) reduces the need to combust cannabis with tobacco, and therefore has the potential to reduce tobacco exposure and the harms associated with it, that this may deliver very high doses of the main psychoactive compound in cannabis, THC. This is together with a more rapid delivery which some users have described as being “psychedelic” due to the very high doses of THC involved – potentially around ten times greater than in skunk. Although, this very high level of THC was not found in the current study on this particular electronic cigarette

“Whilst vaping cannabis substances, called cannabinoids, does indeed remove the harmful effects of tobacco smoke, my concerns about vaping cannabis would be around the use of flavoured cannabis e-cigarettes that could be more popular amongst younger people, who appear most at risk of some of the potential harms associated with heavy and long-term use of cannabis during adolescence. What’s more there is evidence to suggest that consuming cannabis whilst pregnant may have lasting effects on the unborn child, so I would be also be concerned about pregnant women using long-term high dose THC, although further research is needed. I think branding cannabis use through an electronic cigarette as “therapeutic cannavaping” is worrying given that proper randomised controlled trials need to be conducted on any medical intervention to demonstrate their effectiveness, something that is currently lacking in much of the “medical marijuana” market.”

Prof. David Nutt, The Edmond J Safra Chair and Head of the Centre for Neuropsychopharmacology, Imperial College London, said:

“This is an interesting paper and I think it’s a great idea, but this would be illegal in the UK currently. The position in the UK is likely to be that, in the absence of statutory authority, cannabinoids in this form would be either ‘controlled drugs’ for the purposes of the Misuse of Drugs Act 1971 or, if not, psychoactive substances for the purposes of the Psychoactive Substances Act 2016. One could not rule out other statutory measures being relevant too. I hope parliament makes cannabis a medicine soon.”

‘Drug vaping applied to cannabis: Is “Cannavaping” a therapeutic alternative to marijuana?’ by Vincent Varlet et al. published in Scientific Reports on Thursday 26 May 2016.

Declared interests

Dr Michael Bloomfield and Prof. Davit Nutt declare that they have no conflicts of interest.