“Noids” in a nutshell: everything you (don’t) want to know about synthetic cannabimimetics

“Spice” products are synthetic cannabimimetics (SC; also called “synthetic cannabinoids”)-based designer drugs used as a legal alternative to cannabis for their very strong tetrahydrocannabinol (THC)-like effects. The purpose of this paper is to provide an analysis of more recent clinical and pharmacology/toxicology findings relating to SC and describe how they could impact on health, with a particular focus on mental health.

A systematic search and descriptive analysis of the available evidence on psychopathological issues related to misuse was performed here, whilst taking into account the Pubmed/Medline databases, a range of conference proceedings and national/international agencies’ reports.

While THC is a partial agonist, SC are full agonists on the cannabinoid receptors (CB-rs) and the administration of multiple SC can produce additive and/or synergistic agonistic interaction effects on the endocannabinoid system. These levels of strong CB-rs’ activation may be high enough to produce severe physiological and psychological disturbances. The available evidence suggests an existing relationship between SC use and psychosis (“Spiceophrenia”). The acute SC intoxication is usually characterized by tachycardia/hypertension; visual/auditory hallucinations; mydriasis; agitation/anxiety; tachypnoea; nausea/vomiting; and seizures.

The absence of clinical trials and longitudinal studies, together with the heterogeneity of SC compounds does not facilitate a precise assessment of the health risks related to their use, with long-term effects being of particular concern.

Appropriate, non-judgemental, prevention campaigns with a special focus on the differences between SC and cannabis may need to be organized on a large scale. At the same time, clinicians need to be regularly updated about novel psychoactive substances, including SC, to promptly recognize signs/symptoms of intoxication.