As cannabis laws become liberalised in many countries, experts writing in The Lancet Psychiatry argue that there is an urgent need to explore how cannabis use can be made safer.
The authors say that policy makers and researchers should consider regulating cannabis potency, reducing the use of tobacco (e.g. by using vapourisers), and exploring how the chemical composition of cannabis could be modified to reduce harm without altering the pleasurable effects of the drug.
In the past 40 years, the potency of cannabis has on average doubled worldwide and there is evidence of a greater number of people seeking help for cannabis use disorders in the UK, Europe, and USA.
Despite prohibitive laws on possession and use of cannabis being introduced in the 1960s, cannabis use has increased in most parts of the world, suggesting the laws have had little effect on use and abuse. Uruguay and a number of US states, including California, Oregon, Alaska, Maine, Massachusetts, Washington, Nevada, and Colorado allow cannabis to be sold for recreational purposes. Canada is set to legalise its recreational use in 2017 and several European countries, including Portugal, Spain and the Netherlands, have lessened or abolished sanctions on possession and use.
The main active compounds found in cannabis are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). High potency cannabis is high in THC with low (or absent) levels of CBD. This variety is commonly known as sinsemilla (Spanish meaning "without seed") or sometimes "skunk". Recent evidence suggests that CBD may protect against some of the detrimental effects of THC such as memory impairment and paranoia.
Dr Tom Freeman, a co-author and Senior Research Fellow for the Society for the Study of Addiction said: "In the last eight years, the number of people in the UK entering specialist treatment for cannabis increased by over 50%. During the same time period, street cannabis has become increasingly strong with high levels of THC and little or no CBD. Further research on CBD is now needed - both to investigate its potential role in mitigating the harmful effects of THC in cannabis, but also as a potential treatment for the minority of people who develop problematic cannabis use. Efforts to reduce the common practice of mixing cannabis with tobacco could potentially prevent people progressing to nicotine dependence, providing a substantial benefit for public health."
Source article: Can we make cannabis safer? Amir Englund, Tom P Freeman, Robin M Murray, Philip McGuire, The Lancet Psychiatry, doi: 10.1016/S2215-0366(17)30075-5, published 1 March 2017.