Description

Phenmetrazines (phenylmorpholines) are a structural subgroup of stimulants. Preludin, a phenmetrazine, was developed in the mid-1950s as an appetite suppressant and is a potent substrate for dopamine and norepinephrine transporters. So far, no phenmetrazine has been placed under international control since 2015.


Chemical structure

The synthetic approaches to phenmetrazines can easily be adapted to access ring-modified analogues. Thirteen novel phenmetrazines have been reported to UNODC, of which eight are shown below (Figure 1).

Figure 1: Chemical structures of phenmetrazine derived NPS



Note: The structural differences are highlighted in red.
Source: UNODC, The challenge of New Psychoactive Substances - A technical update (United Nations publication, 2024).


Commonly used forms

On the illicit market, central nervous system stimulants are normally encountered in orally active solid-dosage forms (e.g., powder or pills) and can be insufflated or inhaled, swallowed (often wrapped in cigarette papers, colloquially known as “bombing”), smoked, and less commonly injected or used rectally (Figure 2).

Figure 2: Stimulants commonly used forms



Source: UNODC, The challenge of New Psychoactive Substances - A technical update (United Nations publication, 2024).

Reported adverse effects

There is limited pharmacological and toxicological data on many phenmetrazine analogues. Symptoms commonly associated with acute, non-fatal, intoxications involving 3-fluorophenmetrazine include tachycardia, reduced level of consciousness, agitation/anxiety, and delirium. Less common symptoms such as miosis, seizures, and hypertension are also observed. Figure 3 shows reported effects of stimulants.

Figure 3: Reported effects of stimulants



Source: UNODC, The challenge of New Psychoactive Substances - A technical update (United Nations publication, 2024).

References

UNODC, The challenge of New Psychoactive Substances - A technical update (United Nations publication, 2024).

UNODC, Early Warning Advisory on New Psychoactive Substances Dashboard, accessed 27 September 2024.

Last update: 30/09/2024