Hallucinogens and dissociative agents naturally growing in the United States

Opioid receptors and legal highs: Salvia divinorum and Kratom

Salvia divinorum and Mitragyna speciosa ("Kratom"), two unscheduled dietary supplements whose active agents are opioid receptor agonists, have discrete psychoactive effects that have contributed to their increasing popularity. Salvia divinorum contains the highly selective kappa- opioid receptor agonist salvinorin A; this compound produces visual hallucinations and synesthesia. Mitragynine, the major alkaloid identified from Kratom, has been reported as a partial opioid agonist producing similar effects to morphine. An interesting minor alkaloid of Kratom, 7-hydroxymitragynine, has been reported to be more potent than morphine. Both Kratom alkaloids are reported to activate supraspinal mu- and delta- opioid receptors, explaining their use by chronic narcotics users to ameliorate opioid withdrawal symptoms. Despite their widespread Internet availability, use of Salvia divinorum and Kratom represents an emerging trend that escapes traditional methods of toxicologic monitoring. The purpose of this article is to familiarize toxicologists and poison control specialists with these emerging psychoactive dietary supplements.

"Research chemicals": tryptamine and phenethylamine use among high-risk youth

Tryptamines and phenethylamines are two broad categories of psychoactive substances with a long history of licit and illicit use. Profiles of users of recently emerging tryptamines and phenethylamines are nonexistent, however, since surveillance studies do not query the use of these substances. This manuscript describes the types, modes of administration, onset of use, and context of use of a variety of lesser known tryptamines and phenethylamines among a sample of high-risk youth. Findings are based upon in-depth interviews with 42 youth recruited in public settings in Los Angles during 2005 and 2006 as part of larger study examining health risks associated with injecting ketamine. Youth reported that their use of tryptamines and phenethylamines was infrequent, spontaneous, and predominately occurred at music venues, such as festivals, concerts, or raves. Several purchased a variety of these "research chemicals" from the Internet and used them in private locations. While many described positive experiences, reports of short-term negative health outcomes included nausea, vomiting, diarrhea, disorientations, and frightening hallucinations. These findings, based upon pilot study data, move toward an epidemiology of tryptamine and phenethylamine use among high-risk youth.

Herbal drugs of abuse: an emerging problem

Some herbal products are emerging as popular drugs for recreational abuse. Plant and herbal supplements used recreationally can have a wide spectrum of clinical effects ranging from euphoric and stimulant effects to hallucinogenic experiences. Despite the potential for abuse, addiction, and serious adverse effects, there may be a false perception that these products are all safe, legal, and organic. These perceptions and the ease of accessibility to herbal products could result in greater potential for recreational abuse and subsequent complications presenting to emergency departments. Health care professionals must be cognizant of this emerging problem as increased media coverage and marketing have made these products accessible and recognizable to many young adults and teenagers.

The hallucinogen derived from Salvia divinorum, salvinorin A, has kappa-opioid agonist discriminative stimulus effects in rats

Data from clinical and preclinical studies converge implicating the plant-derived hallucinogen salvinorin A as an important pharmacologic tool; this psychoactive compound may expand scientific understandings on mammalian kappa-opioid receptor systems. Human salvinorin A effects, consistent with kappa-opioid receptor agonism, include antinociception, sedation, dysphoria and distorted perceptions. The experiments reported here measured salvinorin A (1-3mg/kg, i.p.) discriminative stimulus properties in male Sprague-Dawley rats conditioned to recognize the discriminative stimulus cue generated by the well characterized kappa-opioid agonist U-69593 (0.56 mg/kg, i.p.). At three distinct active doses, salvinorin A fully substituted for U-69593 without altering response rates. The lever choice pattern in U-69593 trained animals reverted to vehicle lever responding when a kappa selective antagonist compound, nor-BNI (4.5 nM, i.c.v.) was administered 1h prior to salvinorin A, yet nor-BNI alone failed to impact the rate or pattern of subject responses. These findings confirm and extend results published after similar drug discrimination tests were performed in rhesus monkeys. The discussion section of this article highlights public concern over salvinorin A misuse and emphasizes several potential pharmacotherapeutic applications for salvinorin A or analogue compounds.

Determination of muscimol and ibotenic acid in Amanita mushrooms by high-performance liquid chromatography and liquid chromatography-tandem mass spectrometry

A reliable analytical method was developed for the quantification and identification of muscimol (MUS) and ibotenic acid (IBO), the toxic constituents of Amanita muscaria and Amanita pantherina. MUS and IBO were extracted from mushrooms by aqueous methanol and derivatized with dansyl chloride (DNS-Cl). After extraction with ethyl acetate and evaporation of the solvent, the residue was ethylated with 1.25 M hydrogen chloride in ethanol. The resulting derivatives were quantified by high-performance liquid chromatography with UV detection and identified by liquid chromatography electrospray ionization tandem mass spectrometry. Calibration curves were linear in the range of 25-2500 ppm for MUS and 40-2500 ppm for IBO, respectively. This method was successfully applied to identify and quantify MUS and IBO in Amanita mushrooms naturally grown and circulated in the drug market.

Decreased prepulse inhibition and increased sensitivity to muscarinic, but not dopaminergic drugs in M5 muscarinic acetylcholine receptor knockout mice

RATIONALE

Schizophrenic patients show decreased measures of sensorimotor gating, such as prepulse inhibition of startle (PPI). In preclinical models, these measures may be used to predict antipsychotic activity. While current antipsychotic drugs act largely at dopamine receptors, the muscarinic acetylcholine receptors offer promising novel pharmacotherapy targets. Of these, the M(5) receptor gene was recently implicated in susceptibility to schizophrenia. Due to the lack of selective ligands, muscarinic receptor knockout mice have been generated to elucidate the roles of the five receptor subtypes (M(1)-M(5)).

OBJECTIVES

Here, we used M(5) receptor knockout (M(5)-/-) mice to investigate the involvement of M(5) receptors in behavioral measures pertinent to schizophrenia. We tested the hypothesis that disruption of M(5) receptors affected PPI or the effects of muscarinic or dopaminergic agents in PPI or psychomotor stimulation.

MATERIALS AND METHODS

We measured PPI in M(5)-/-, heterozygous and wild-type mice without drugs, and with clozapine (0.56-3.2 mg/kg) or haloperidol (0.32-3.2 mg/kg) alone, and as pretreatment to D: -amphetamine. In addition, we evaluated locomotor stimulation by the muscarinic antagonist trihexyphenidyl (0.56-56 mg/kg) and by cocaine (3.2-56 mg/kg).

RESULTS

The M(5)-/- mice showed decreased PPI relative to wild-type mice, and clozapine appeared to reduce this difference, while haloperidol increased PPI regardless of genotype. The M(5)-/- mice also showed more locomotor stimulation by trihexyphenidyl than wild-type mice, while cocaine had similar effects between genotypes.

CONCLUSIONS

These data suggest that disruption of the M(5) receptor gene affected sensorimotor gating mechanisms, increased sensitivity to clozapine and to the psychostimulant effects of muscarinic antagonists without modifying the effect of dopaminergic drugs.

Increased frontal and paralimbic activation following ayahuasca, the pan-Amazonian inebriant

RATIONALE

Ayahuasca is a South American psychoactive plant tea which contains the serotonergic psychedelic N,N-dimethyltryptamine (DMT) and monoamine-oxidase inhibitors that render DMT orally active. Previous investigations with ayahuasca have highlighted a psychotropic effect profile characterized by enhanced introspective attention, with individuals reporting altered somatic perceptions and intense emotional modifications, frequently accompanied by visual imagery. Despite recent advances in the study of ayahuasca pharmacology, the neural correlates of acute ayahuasca intoxication remain largely unknown.

OBJECTIVES

To investigate the effects of ayahuasca administration on regional cerebral blood flow.

METHODS

Fifteen male volunteers with prior experience in the use of psychedelics received a single oral dose of encapsulated freeze-dried ayahuasca equivalent to 1.0 mg DMT/kg body weight and a placebo in a randomized double-blind clinical trial. Regional cerebral blood flow was measured 100-110 min after drug administration by means of single photon emission tomography (SPECT).

RESULTS

Ayahuasca administration led to significant activation of frontal and paralimbic brain regions. Increased blood perfusion was observed bilaterally in the anterior insula, with greater intensity in the right hemisphere, and in the anterior cingulate/frontomedial cortex of the right hemisphere, areas previously implicated in somatic awareness, subjective feeling states, and emotional arousal. Additional increases were observed in the left amygdala/parahippocampal gyrus, a structure also involved in emotional arousal.

CONCLUSIONS

The present results suggest that ayahuasca interacts with neural systems that are central to interoception and emotional processing and point to a modulatory role of serotonergic neurotransmission in these processes.

New Drugs of Abuse in North America

The term "drugs of abuse" usually brings to mind traditional street drugs, such as cocaine, heroin, marijuana, and methamphetamine. The drug scene, however, is constantly evolving. As various law enforcement agencies pursue and dismantle distribution and pro-duction organizations of the usual drugs of abuse, dealers and users are turning to less known, more accessible, and often currently licit substances. The widespread growth of the Internet with its vast distribution of information has increased the accessibility ofa host of substances and facilitated synthesis and production of various substances by individuals. This article discusses several new and emerging abused substances, including new synthetic variations, plants, and pharmaceuticals diverted for abuse.

Analysis of hallucinogenic constituents in Amanita mushrooms circulated in Japan

The constituents of seven mushrooms sold as Amanita muscaria or Amanita pantherina (five A. muscaria and two A. pantherina) and four "extracts purported to contain A. muscaria" products that are currently circulated in Japan were determined. All mushroom samples were identified as A. muscaria or A. pantherina by macroscopic and microscopic observation. The dissociative constituents, ibotenic acid (IBO) and muscimol (MUS), were extracted with 70% methanol twice and determined by gas chromatography/mass spectrometry. The IBO (as the hydrate)/MUS contents were in the range of <10-2845ppm/46-1052ppm in the cap of A. muscaria and 188-269ppm/1554-1880ppm in the cap of A. pantherina. In the caps, these compounds had a tendency to be more concentrated in the flesh than in the cuticle. On the other hand, the IBO/MUS contents in the stem were far lower than in the caps. In the "extracts purported to contain A. muscaria" products, IBO/MUS were detected below the lower limit of calibration curve (<10ppm/<25ppm) or not detected. However, these samples contained other psychoactive compounds, such as psychoactive tryptamines (5-methoxy-N,N-diisopropyltryptamine and 5-methoxy-N,N-dimethyltryptamine), reversible monoamine oxidase inhibitors (harmine and harmaline) and tropane alkaloids (atropine and scopolamine), which were not quantified. This is the first report of the chemical analysis of Amanita mushrooms that are circulated in the drug market.

The hallucinogenic herb Salvia divinorum and its active ingredient salvinorin A inhibit enteric cholinergic transmission in the guinea-pig ileum

Salvia divinorum is a widespread hallucinogenic herb traditionally employed for divination, as well as a medicament for several disorders including disturbances of gastrointestinal motility. In the present study we evaluated the effect of a standardized extract from the leaves of S. divinorum (SDE) on enteric cholinergic transmission in the guinea-pig ileum. SDE reduced electrically evoked contractions without modifying the contractions elicited by exogenous acetylcholine, thus suggesting a prejunctional site of action. The inhibitory effect of SDE on twitch response was abolished by the opioid receptor antagonist naloxone and by the kappa-opioid antagonist nor-binaltorphimine, but not by naltrindole (a delta-opioid receptor antagonist), CTOP (a mu-opioid receptor antagonist), thioperamide (a H(3) receptor antagonist), yohimbine (an alpha(2)-receptor antagonist), methysergide (a 5-hydroxytryptamine receptor antagonist), N(G)-nitro-L-arginine methyl ester (an inhibitor of NO synthase) or apamin (a blocker of Ca(2+)-activated K(+) channels). Salvinorin A, the main active ingredient of S. divinorum, inhibited in a nor-binaltorphimine- and naloxone-sensitive manner electrically induced contractions. It is concluded that SDE depressed enteric cholinergic transmission likely through activation of kappa-opioid receptors and this may provide the pharmacological basis underlying its traditional antidiarrhoeal use. Salvinorin A might be the chemical ingredient responsible for this activity.

Hallucinogenic botanicals of America: A growing need for focused drug education and research

Botanical sources for medicines in America have been known since long before the arrival of Columbus. Nevertheless, both scientists and the general public are often unaware that some of these botanical drugs are also potent intoxicants. We provide a quick overview of hallucinogenic and dissociative drugs harvested from nature or that are openly and legally cultivated in the United States. Examples of harmful outcomes reported in the media are contrasted with existing responsible ingestion by others, some of whom have the protected right to do so for traditional or sacramental religious purposes. Despite an ongoing and expensive effort to warn people of the potential harms of recreational drug use, little is known about the extent of use of these psychoactive botanicals, and the recent explosion of information available via the Internet could herald a storm of morbidity to come. Mounting more targeted research and educational efforts today may reduce later use and abuse, inform society about the special circumstances of religious use, and better prepare clinicians and other health care providers about the issues involved when people choose to indigenously source psychoactive drugs for human consumption.

Emerging drugs of abuse

Several new and emerging substances are being diverted for abuse. Most of these emerging abused substances do not cause traditional drug screens to turn positive. The health effects of these substances have not yet been fully elucidated. Health care providers should be aware of the existence of these new abused substances.

The most widely recognized mushroom: chemistry of the genus Amanita

Many review papers have been published on mushrooms of the genus Amanita, as these are well known to both scientific and lay audiences, probably due to the toxic and/or hallucinogenic properties of some species. This article aims to supplement the content of previous reviews by categorizing all of the natural products isolated from any species in the genus Amanita. These compounds are subdivided into six major structural types, and references are provided for all species that have been examined chemically.