The International Drug Control Conventions of 1961 and 1971 mandate WHO to make recommendations to the United Nations Secretary-General on the need for and level of international control of psychoactive substances according to the advice of its independent scientific advisory body, the ECDD. At its forty-fourth meeting, the ECDD critically reviewed five new psychoactive substances, comprising one synthetic cannabinoid receptor agonist (4F-MDMB-BICA), two novel synthetic opioids (brorphine and metonitazene) and two cathinones/stimulants (eutylone and benzylone). These substances had not previously been reviewed formally by WHO and are currently not under international control. A critical review of the use of each substance and its effects was undertaken so that the Expert Committee could determine whether the information available on these substances justified scheduling or a change in scheduling from that in the 1961 or 1971 Convention. In addition, the meeting pre-reviewed kratom, mitragynine and 7-hydroxymitragynine and phenibut to determine whether the current information justified a critical review. After the Forty-fourth Meeting of the ECDD, WHO endorsed and submitted the following recommendations to the United Nations Secretary General for further consideration by the Commission on Narcotic Drugs.

• 3.1.1 4F-MDMB-BICA
• 3.1.2 Brorphine
• 3.1.3 Metonitazene
• 3.1.3 Eutylone
• 3.1.4 Benzylone
• 3.2.1 Kratom (Mitragyna speciosa), mitragynine and 7-hydroxymitragynine
• 3.2.2 Phenibut