The definition New psychoactive substances (NPS) refers to emerging drugs whose chemical structures are similar to other psychoactive compounds but not identical, representing a “legal” alternative to internationally controlled drugs. There are many categories of NPS, such as synthetic cannabinoids, synthetic cathinones, phenylethylamines, piperazines, ketamine derivatives and tryptamines. Tryptamines are naturally occurring compounds, which can derive from the amino acid tryptophan by several biosynthetic pathways: their structure is a combination of a benzene ring and a pyrrole ring, with the addition of a 2-carbon side chain. Tryptamines include serotonin and melatonin as well as other compounds known for their hallucinogenic properties, such as psilocybin in ‘Magic mushrooms’ and dimethyltryptamine (DMT) in Ayahuasca brews.Aim: To review the scientific literature regarding tryptamines and their derivatives, providing a summary of all the available information about the structure of these compounds, their effects in relationship with the routes of administration, their pharmacology and toxicity, including articles reporting cases of death related to intake of these substances.Methods: A comprehensive review of the published scientific literature was performed, using also non peer-reviewed information sources, such as books, government publications and drug user web fora.Conclusions: Information from Internet and from published scientific literature, organized in the way we proposed in this review, provides an effective tool for specialists facing the emerging NPS threat to public health and public security, including the personnel working in Emergency Department.

The 3Ks (kava, kratom and khat) are herbals that can potentially induce liver injuries. On the one hand, growing controversial data have been reported about the hepatotoxicity of kratom, while, on the other hand, even though kava and khat hepatotoxicity has been investigated, the hepatotoxic effects are still not clear. Chronic recreational use of kratom has been associated with rare instances of acute liver injury. Several studies and case reports have suggested that khat is hepatotoxic, leading to deranged liver enzymes and also histopathological evidence of acute hepatocellular degeneration. Numerous reports of severe hepatotoxicity potentially induced by kava have also been highlighted, both in the USA and Europe. The aim of this review is to focus on the different patterns and the mechanisms of hepatotoxicity induced by “the 3Ks”, while trying to clarify the numerous aspects that still need to be addressed.

No abstract

Background In those countries where cannabis use is still illegal, some manufacturers started producing and selling “light cannabis”: dried flowering tops containing the psychoactive principle Δ-9-tetrahydrocannabinol (THC) at concentrations lower than 0.2% together with variable concentration of cannabidiol (CBD). We here report a pilot study on the determination of cannabinoids in the oral fluid and urine of six individuals after smoking 1 g of “light cannabis”. Methods On site screening for oral fluid samples was performed, as a laboratory immunoassay test for urine samples. A validated gas chromatography-mass spectrometry (GC-MS) method was then applied to quantify THC and CBD, independently from results of screening tests. Results On site screening for oral fluid samples, with a THC cut-off of 25 ng/mL gave negative results for all the individuals at different times after smoking. Similarly, negative results for urine samples screening from all the individuals were obtained. Confirmation analyses showed that oral fluid THC was in the concentration range from 2.5 to 21.5 ng/mL in the first 30 min after smoking and then values slowly decreased. CBD values were usually one order of magnitude higher than those of THC. THC-COOH, the principal urinary THC metabolite, presented the maximum urinary value of 1.8 ng/mL, while urinary CBD had a value of 15.1 ng/mL. Conclusions Consumers of a single 1 g dose of “light cannabis” did not result as positive in urine screening, assessing recent consumption, so that confirmation would not be required. Conversely, they might result as positive to oral fluid testing with some on-site kits, with THC cut-off lower than 25 ng/mL, at least in the first hour after smoking and hence confirmation analysis can be then required. No conclusions can be drawn of eventual chronic users.

Mephedrone is a β-ketoamphetamine belonging to the family of synthetic cathinones, an emerging class of designer drugs known for their hallucinogenic and psychostimulant properties as well as for their abuse potential. The aim of this review was to examine the emerging scientific literature on the possible mephedrone-induced neurotoxicity, yet not well defined due to the limited number of experimental studies, mainly carried on animal models. Relevant scientific articles were identified from international literature databases (Medline, Scopus, etc.) using the keywords: “Mephedrone”, “4-MMC,” “neurotoxicity,” “neuropharmacology”, “patents”, “monoamine transporters” and “neurochemical effects”. Of the 498 sources initially found, only 36 papers were suitable for the review. Neurotoxic effect of mephedrone on 5-HT and DA systems remains controversial. Although some studies in animal models reported no damage to DA nerve endings in the striatum and no significant changes in brain monoamine levels, some others suggested a rapid reduction in 5-HT and DA transporter function. Persistent serotonergic deficits were observed after binge like treatment in a warm environment and in both serotonergic and dopaminergic nerve endings at high ambient temperature. Oxidative stress cytotoxicity and an increase in frontal cortex lipid peroxidation were also reported. In vitro cytotoxic properties were also observed, suggesting that mephedrone may act as a reductant agent and can also determine changes in mitochondrial respiration. However, due to the differences in the design of the experiments, including temperature and animal model used, the results are difficult to compare. Further studies on toxicology and pharmacology of mephedrone are therefore necessary to establish an appropriate treatment for substance abuse and eventual consequences for public health.