For nearly 60 years the United Nations has designated cannabis as dangerous, consequently limiting research into its potential benefits. However the World Health Organisation – the United Nations public health agency based in Geneva – has requested this designation be dropped and its medical benefits recognised.

In November last year, the WHO Expert Committee on Drug Dependence recommended cannabis resin and other products be downgraded from a schedule IV to a schedule I drug under international law.

Schedule IV is the strictest category outlined in the 1961 Single Convention on the Narcotic Drugs Treaty, meaning cannabis is currently treated in the same way as heroin, severely restricting scientists who want to investigate the plant in the search for potential therapies.

The committee also recommended that THC – the main psychoactive ingredient in cannabis – should be designated as a schedule I drug and that cannabis with less than than 0.2 percent THC – effectively the cannabinoid CBD – should be removed from all international drug control conventions.

The WHO says that it has not reviewed cannabis since it was scheduled in 1961 because there was not sufficient scientific research into the health effects of the drug. However, the organisation said that in recent years this situation had changed as attitudes toward the drug shifted.

The move has been described as a ‘major breakthrough in international cannabis policy, and a clear victory of evidence over politics’. Many countries rely on the Treaty’s schedules and other international bodies such as the INCB (International Narcotics Control Board) will now provide guidance to countries based on this new position.

Approving WHO’s recommendations will serve as a recognition by the UN of the cannabis’ therapeutic properties, said Ethan Russo, MD, a neurologist and director of research and development of the International Cannabis and Cannabinoids Institute.

“Governments have an obligation to translate provision of the treaties in their national legislation so this definitely will have an impact and all countries will have to modify the position on THC in their legislation.

“It is gratifying that the World Health Organisation has recognised the scientific fact that cannabis and its derivatives have demonstrable therapeutic properties and can be the base for safe and effective medicines,” he said.

The new scheduling was set to be approved by UN Commission on Narcotic Drugs in March this year but this has been delayed.