Cannabis use in Europe: Current trends and public health concerns.

In this contribution, I summarize recent trends of cannabis use in Europe and their public health implications. The first trend refers to an increase of treatment demand for cannabis problems by 76% while prevalence of cannabis use remained largely stable in the same period, based on available data. There are good reasons to assume that this trend reflects increases in the prevalence of cannabis use disorders, however, data to support this claim are not available. Potential drivers for a rising prevalence of cannabis use disorders comprise changes in consumption patterns and increasing levels of THC in available cannabis products. While an increasing prevalence of cannabis use disorders seem likely, the estimates of the Global Burden of Disease studies suggest the opposite. The second trend refers to an emerging market for cannabidiol (CBD) products in European countries, where regulations on CBD are lacking. Given the lack of data on users of CBD products, it can hardly be assessed if current abstainers will initiate using other cannabis products after trying CBD products for medicinal or recreational purposes. However, regulations should be implemented and enforced in order to make CBD products safer for consumers, for instance by ensuring reliable potency levels and by reducing the presence of toxic substances through quality control measures. In summary, a substantial transition of the epidemiology of cannabis use is under way, accompanied by changes in potency, treatment demand and new products. In order to assess the public health implications of this transition, data on population exposure of specific cannabinoids are required.