Electronic cigarettes (e-cigarettes) are increasing in popularity with 19% of UK smokers reporting to have used them. The ability to regulate the evaporation temperature in newer electronic nicotine delivery systems (ENDS) facilitates the potential for use of these devices to 'vape' cannabis, novel psychoactive substances (NPS) and other recreational drugs. Vaping cannabis does have the potential to reduce tobacco use and combustible cannabis/tobacco-related disease, but with over one-third of UK adults reporting life-time use of recreational drugs and increasing e-cigarette uptake in adolescent groups the misuse of these devices poses a serious potential public health risk. Further work is therefore urgently required to inform the appropriate treatment and primary prevention strategies for this emerging issue.