A leading independent scientific committee on drugs has conducted a review of all the existing research regarding the health effects of marijuana, which it hopes the World Health Organization (WHO) will use as a basis to reassess the science behind the global ban on the drug.
An international treaty known as the Single Convention on Narcotic Drugs led to cannabis being classified as a Schedule 1 substance back in 1961. This means that it is considered to be highly addictive and have no therapeutic value. However, in the more than five decades since this arrangement was put in place, our understanding of marijuana’s effects has changed dramatically, which is why experts are now calling for a reappraisal of this scheduling.
The Single Convention on Narcotic Drugs is supposed to base all of its decisions on scientific evidence provided by the WHO’s Expert Committee on Drug Dependence (ECDD). However, the ECDD has never conducted a review into the effects of cannabis, meaning that the last body to do so was the Health Committee of the League of Nations in 1935.
With the ECDD set to meet in November, a committee called DrugScience – which is made up of some of the world’s leading experts on drugs – has compiled a full review of all the evidence for and against cannabis’s inclusion in Schedule 1.
"DrugScience provides a unique opportunity... to initiate a critical review process of cannabis and cannabis resin for their scheduling under the Single Convention on Narcotic Drugs," explain the authors.
Medications containing cannabis are now licensed in 28 different countries. Africa Studio/Shutterstock
Among the issues raised by the report is that, according to the ECDD’s official criteria, Schedule 1 is reserved for drugs that are at least as addictive as codeine. However, codeine is an opioid, meaning it binds to the opiate receptors in the central nervous system, while marijuana contains compounds that bind to cannabinoid receptors, so it is not possible to directly compare the two.
By analyzing all the existing research on cannabis, the authors found that there is evidence that the drug leads to dependence by altering the way that a cannabinoid receptor called CB1R works, although evidence suggests that this returns to normal soon after use of the drug is stopped.
The report also reveals that there is a potential connection between cannabis use and psychosis, and that the drug also appears to have therapeutic value – particularly for the treatment of multiple sclerosis, chronic pain and chemotherapy-related nausea – which explains why medicines containing cannabis are currently licensed in 28 countries.
Though the review does not pass an overall judgment on how cannabis should be scheduled, the authors insist that much of the evidence they present suggests that the scientific justification for the current restrictions on the drug require urgent reconsideration.
