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At least 19 recordsLinked to original sources
PubMed2006

Evidence for a hallucinogen dependence syndrome developing soon after onset of hallucinogen use during adolescence.

This study uses latent class methods and multiple regression to shed light on hypothesized hallucinogen dependence syndromes experienced by young people who have recently initiated hallucinogen use. It explores possible variation in risk. The study sample, identified within public-use data files of the 1999 National Household Survey on Drug Abuse (NHSDA), consists of 1186 recent-onset hallucinogen users, defined as having initiated hallucinogen use within 24 months of assessment (median elapsed time since onset of use -12 to 13 months). The recent-onset users in this sample were age 12 to 21 at the time of assessment and were between the ages of 10 and 21 at the time of their first hallucinogen use. The NHSDA included items to assess seven clinical features often associated with hallucinogen dependence, which were used in latent class modelling. Latent class analysis, in conjunction with prior theory, supports a three-class solution, with 2% of recent-onset users in a class that resembles a hallucinogen dependence syndrome, whereas 88% expressed few or no clinical features of dependence. The remaining 10% may reflect users who are at risk for dependence or in an early stage of dependence. Results from latent class regressions indicate that susceptibility to rapid transition from first hallucinogen use to onset of this hallucinogen dependence syndrome might be influenced by hallucinogenic compounds taken (for example, estimated relative risk, RR = 2.4, 95% CI = 1.6, 7.6 for users of MDMA versus users of LSD). Excess risk of rapid transition did not appear to depend upon age, sex, or race/ethnicity.

Adolescent↗
PubMed2006

Who is becoming hallucinogen dependent soon after hallucinogen use starts?

This study, based upon epidemiological survey data from the United States (U.S.) National Household Surveys on Drug Abuse (NHSDA) from 2000 to 2001, presents new estimates for the risk of developing a hallucinogen dependence syndrome within 24 months after first use of any hallucinogen (median elapsed time approximately 12 months). Subgroup variations in risk of becoming hallucinogen dependent also are explored. Estimates are derived from the NHSDA representative samples of non-institutionalized U.S. residents ages 12 and older (n=114,241). A total of 2035 respondents had used hallucinogens for the first time within 24 months prior to assessment. An estimated 2-3% of these recent-onset hallucinogen users had become dependent on hallucinogens, according to the NHSDA DSM-IV computerized diagnostic algorithm. Controlling for sociodemographic and other drug use covariates, very early first use of hallucinogens (age 10-11 years) is associated with increased risk of hallucinogen dependence (p<0.01). Excess risk of developing hallucinogen dependence was found in association with recent-onset use of mescaline; excess risk also was found for recent-onset users of ecstasy and of PCP. This study's evidence is consistent with prior evidence on a tangible but quite infrequent dependence syndrome soon after the start of hallucinogen use; it offers leads that can be confirmed or disconfirmed in future investigations.

Adolescent↗
PubMed1981

Activity of a non-hallucinogenic ergoline derivative, lisuride, in an animal behavior model for hallucinogens.

The behavioral effects of IP administration of lisuride, a non-hallucinogenic iso-lysergic acid amide analog structurally related to d-lysergic acid diethylamide (LSD), were examined in 15 cats. Ten animals were given saline or 6.25, 12.5, 25, 50, or 100 micrograms/kg of lisuride and observed for 1 h by a rater blind to dose. There was a statistically significant effect of lisuride dose on the frequency of occurrence of the behaviors limb flicking, grooming, and abortive grooming. A time-course study with five cats at the most effective lisuride dose, 50 micrograms/kg, revealed that the frequencies of occurrence of these behaviors reached a maximum during the first 2 h post dose, and were comparable to frequencies after saline by 6 h post dose. An acute tolerance study with four cats scored for 90 min post dose revealed no significant tolerance to a 50 micrograms/kg lisuride test dose administered 6, 24, or 72 h after an initial 50 micrograms/kg dose. Acute cross tolerance studies with four cats scored for 90 min after an initial dose of 50 micrograms/kg of LSD or of lisuride, followed 24 h later by 50 micrograms/kg of lisuride or LSD, revealed no significant cross tolerance. The potency of lisuride relative to LSD was evaluated in six cats that were scored for 60 min following 25 and 50 micrograms/kg of LSD and of lisuride. On a molar basis, scores after lisuride were 51% and 67% those after LSD for limb flicking and grooming. These results indicate that lisuride, a non-hallucinogenic iso-lysergic acid derivative, is a false positive in the animal behavior model for hallucinogens.

Animals↗
PubMed1984

Monoamine oxidase inhibitors in South American hallucinogenic plants Part 2: Constituents of orally-active Myristicaceous hallucinogens.

Alkaloid constituents in Myristicaceous bark and leaf samples and in purportedly hallucinogenic preparations derived from Myristicaceous sources were qualitatively and quantitatively analyzed using TLC, GC, alkaloid precipitation tests and GC/MS. Fourteen of the 27 bark and leaf samples analyzed contained detectable amounts of alkaloids. The major bases were N,N-dimethyltryptamine (DMT) and/or 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT); much smaller amounts of tryptamine and/or N-methyl-tryptamine (NMT) were also usually present. beta-Carbolines were not detected in the bark or leaf samples. Considerable variation in alkaloid profiles was found, extending to different collections of the same species. Fourteen of the 20 Virola samples contained alkaloids; none of the 6 Iryanthera species had detectable alkaloids. Osteophloem platyspermum contained an indolic base, identified as N-methyl-tryptophan methyl ester. Seven samples of an orally-ingested drug made from Virola spp. were analyzed. All except one contained substantial amounts of tryptamines; the types and proportions of tryptamines present varied greatly between samples. Samples of Yanomama snuff including various admixtures were analyzed and all components but one contained tryptamines. The drug samples having the highest concentrations of alkaloids contained 15-20 mg/g dry wt while the Myristicaceous bark and leaf samples had much lower concentrations ranging from 0.04 to 0.25 mg/g dry wt. beta-Carbolines were detected as trace constituents in only two of the Myristicaceous drug samples. Four Myristicaceous paste samples were bioassayed in self-experiments. Two of the samples were devoid of detectable hallucinogenic or physiological activity, while some degree of oral activity was detected in two other samples. The activity of a number of tryptamine derivatives as monoamine oxidase inhibitors (MAOI) was investigated using an in vitro enzyme assay. Activity was measured using single compounds and mixtures of compounds and the results were compared to the activity of samples of orally-ingested Myristicaceous pastes. Tryptamine derivatives had significantly less MAOI activity than the activity of beta-carboline derivatives measured in a previous study. Some structural correlations for MAOI activity were found for the tryptamine derivatives. Samples of orally-ingested Myristicaceous pastes were assayed for MAOI activity. The inhibition elicited by the paste samples was closely matched by mixtures of tryptamine standards having comparable proportions and concentrations.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1986

A primate model for the study of hallucinogens.

An animal model for studying the actions of hallucinogenic drugs using primate social colonies is presented. Although hallucinogens induce a number of behavioral changes in this paradigm, one emergent behavior, limb jerks, appears to be selectively induced by three classes of hallucinogens in doses which correlate with those reported to be hallucinogenic in humans. Several non-hallucinogenic congeners of hallucinogens failed to significantly elicit this response. Other behavioral changes induced by hallucinogens in monkeys such as ptosis and social withdrawal may be useful in studying aspects of hallucinogen intoxication other than hallucinations, or psychosis in general. Upon daily administration, tolerance developed to all hallucinogens tested except two, as is seen in humans. Moreover, cross-tolerance between hallucinogens could be demonstrated. Further experiments with the hallucinogen 5-methoxy N,N-dimethyltryptamine revealed that although certain individual behaviors could be antagonized by serotonin antagonists, dopamine antagonists, and physostigmine, no drug completely reversed the behavioral abnormalities induced by this hallucinogen. It is suggested that this paradigm, which offers an hallucinogen-induced behavior which correlates well with the human hallucinogen response and permits observation of a wide variety of other potentially relevant behaviors in primates, may be useful in developing and testing theories of hallucinogenic drug action. It may be especially valuable in view of the present difficulties of conducting hallucinogen research in humans.

Animals↗
PubMed1975

Screening hallucinogenic drugs: systematic study of three behavioral tests.

The effects of several hallucinogenic and non-hallucinogenic drugs have been studied on three behavioral tests proposed as useful indexes of hallucinogenic activity: "head-twitching" in mice, defecation in an open-field, and suppression of responding on a differential reinforcement of low rates (DRL) schedule of reinforcement. According to the original propositions, after administration of hallucinogenic agents the frequency of head-twitches would increase in mice, the defecation of rats in an open field would decrease without consistent change in ambulation, rearing and grooming, and the responding of rats on a DRL schedule would yield a typical cumulative record pattern. It was found that the head-twitch test was sensitive to mescaline and LSD-25, but not to delta9-THC or to myristicin and elemicin. Besides, the data on interobserver agreement suggested there is a high degree of subjectivity involved in assessing this response. In the open-field test, non-hallucinogenic drugs such as chlorpromazine and apomorphine fell into the hallucinogenic pattern proposed. In addition, the post-injection interval selected seemed to critically affect defecation scores. The DRL "hallucinogenic" pattern occurred nonspecifically after administration of hallucinogenic and non-hallucinogenic drugs. It was concluded that the three tests have limited value for screening purposes.

5-Hydroxytryptophan↗
PubMed2003

Hallucinogens: an update.

Research of hallucinogen abuse rarely extends beyond epidemiology and observed pathology. Even less research has been completed on the special circumstances surrounding the religious use of hallucinogens or on potential therapeutic applications. Rather than offer another basic review on the well-known hazards of illicit hallucinogen use, this paper provides an overview and practice recommendations on compounds the clinician may be less familiar with, such as the botanical plant Salvia divinorum, the drug 3,4-methylenedioxymethamphetamine ("ecstasy") and synthetic hallucinogen analogs. The often-warned, but rarely occurring, hazard of hallucinogen persisting perception disorder ("flashbacks") is also reviewed with treatment recommendations provided. The current status of clinical research with the hallucinogens is presented, with case vignettes suggesting hallucinogens may have anti-addictive applications. The special circumstances surrounding the religious, nondrug use of hallucinogens as sacred sacraments in the US and elsewhere are also presented. It is hoped that the reader will gain a more nuanced understanding of how these physiologically nonaddictive drugs may offer legitimate benefits in modern society. By appreciating that such benefits may one day be borne out by careful, methodologically sound research, clinicians should be better armed in raising the topic of hallucinogen use and abuse with their patients.

Adult↗
PubMed2002

Exposure opportunity as a mechanism linking youth marijuana use to hallucinogen use.

The aim of this study is to shed light upon an observed association between the use of marijuana and hallucinogens (e.g. LSD), with a specific focus on the idea that two separate mechanisms might link marijuana use to hallucinogen use: (1) greater hallucinogen exposure opportunity for marijuana users versus nonusers; (2) increased probability of hallucinogen use for marijuana users versus nonusers, once the opportunity to use hallucinogens has occurred. This work is based on a novel analysis of retrospective, self-report data from more than 40000 young participants in the 1991-1994 National Household Surveys on Drug Abuse (NHSDA), with discrete time survival analysis models. Youths who had used marijuana were substantially more likely than nonusers to have the opportunity to use hallucinogens (estimated unadjusted relative risk, uRR=16.3; 95%. Confidence interval (CI)=14.3-18.6). Once an opportunity to use hallucinogens occurred, marijuana users were more likely than nonusers to initiate hallucinogen use (uRR=12.6; 95% CI=9.0-17.6). This evidence provides a more complete view of interconnections between marijuana use and hallucinogen use, and helps to clarify the pivotal role for drug exposure opportunities. Important next steps will be to understand what accounts for variation in the exposure opportunities experienced by marijuana users, and to understand why some marijuana users do not progress even when they have a chance to do so.

Adolescent↗
PubMed1991

Discriminative stimulus properties of hallucinogens and related designer drugs.

Animals trained to discriminate classical hallucinogens from saline have been used in the past decade to examine other hallucinogenic agents. Time course (onset, duration of action) and locus of action have been studied, SARs have been formulated, and mechanism of action has been investigated in detail. On the basis of DD studies in animals, it was proposed that hallucinogenic agents may produce their actions in humans via a 5-HT2 agonist mechanism and that certain phenalkylamine hallucinogens such as DOM and DOB might constitute the first known examples of 5-HT2 agonists. This led to the development of [3]HDOB and [125I]DOI for use in radioligand binding and autoradiographic studies and to the use of hallucinogen-trained animals as a functional behavioral model of 5-HT2 receptor activation. Animals trained to classical hallucinogens are more recently being used to evaluate novel designer drugs. It can be seen, then, that this paradigm, using hallucinogenic agents as training drugs, has proven to be quite useful for the investigation of hallucinogens and nonhallucinogens alike.

Amphetamine↗
PubMed1982

Neurophysiological effects of hallucinogens on serotonergic neuronal systems.

Low intravenous doses of the hallucinogen d-lysergic acid diethylamide (LSD) markedly suppress the discharge of serotonin (5-HT)-containing neurons in the dorsal raphe nucleus of the rat. Microiontophoretically applied LSD also inhibits the firing of 5-HT neurons, indicating that the inhibitory effect is mediated directing on 5-HT neurons. Forebrain neurons receiving a major serotonergic input are relatively insensitive to LSD. Other indole hallucinogens (i.e., psilocin, dimethyltryptamine, and 5-methoxydimethyltryptamine) also preferentially inhibit raphe firing as compared to postsynaptic forebrain neurons. These observations led to the hypothesis that hallucinogens produce their psychoactive effects by acting preferentially upon 5-HT autoreceptors in the dorsal raphe allowing postsynaptic neurons to escape from the tonic inhibitory action of 5-HT neurons. However, problems exist with the concept that hallucinogens produce their psychoactive effects by disinhibiting postsynaptic neurons. First, the time course of the behavioral and neuronal effects of LSD do not correlate. Second, 5-HT neurons do not become tolerant to the inhibitory actions of LSD. Third, the hallucinogen mescaline fails to directly inhibit 5-HT neurons. Finally, the nonhallucinogen lisuride markedly suppresses the discharges of 5-HT neurons. These observations suggest that postsynaptic actions of hallucinogens may be of prime importance in producing their psychedelic effects. Evidence is presented to suggest that the hallucinogens may act postsynaptically to sensitize both serotonergic and noradrenergic receptors. It is suggested that a mechanism of receptor sensitization, in distinction to disinhibition, might account for the altered perceptual reactivity produced by these drugs.

Animals↗
PubMed2004

Hallucinogens.

Hallucinogens (psychedelics) are psychoactive substances that powerfully alter perception, mood, and a host of cognitive processes. They are considered physiologically safe and do not produce dependence or addiction. Their origin predates written history, and they were employed by early cultures in a variety of sociocultural and ritual contexts. In the 1950s, after the virtually contemporaneous discovery of both serotonin (5-HT) and lysergic acid diethylamide (LSD-25), early brain research focused intensely on the possibility that LSD or other hallucinogens had a serotonergic basis of action and reinforced the idea that 5-HT was an important neurotransmitter in brain. These ideas were eventually proven, and today it is believed that hallucinogens stimulate 5-HT(2A) receptors, especially those expressed on neocortical pyramidal cells. Activation of 5-HT(2A) receptors also leads to increased cortical glutamate levels presumably by a presynaptic receptor-mediated release from thalamic afferents. These findings have led to comparisons of the effects of classical hallucinogens with certain aspects of acute psychosis and to a focus on thalamocortical interactions as key to understanding both the action of these substances and the neuroanatomical sites involved in altered states of consciousness (ASC). In vivo brain imaging in humans using [(18)F]fluorodeoxyglucose has shown that hallucinogens increase prefrontal cortical metabolism, and correlations have been developed between activity in specific brain areas and psychological elements of the ASC produced by hallucinogens. The 5-HT(2A) receptor clearly plays an essential role in cognitive processing, including working memory, and ligands for this receptor may be extremely useful tools for future cognitive neuroscience research. In addition, it appears entirely possible that utility may still emerge for the use of hallucinogens in treating alcoholism, substance abuse, and certain psychiatric disorders.

Alcoholism↗
PubMed2006

Detection and determination of abused hallucinogens in biological material.

OBJECTIVES: Until recently, routine toxicological analysis of some hallucinogens in biological material posed problems which were only resolved after the introduction of modern analytic systems into toxicological laboratories. The most frequent hallucinogens in clinical and forensic toxicology can be grouped as: cannabinoids, tropane alkaloids, N,N-dimethyltryptamine derivatives and synthetic or semisynthetic hallucinogens. METHODS & RESULTS: There are several methods currently used for their analysis. Immunoassay analysis of abused hallucinogens is limited to the cannabinoids. Thin layer chromatography (TLC) is able to detect higher concentrations of 1-nor-delta- 9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH), tropane alkaloids (atropine and scopolamine) and ketamine (synthetic hallucinogen) in urine but for lower concentrations and for some other substances it lacks sensitivity. A reliable solution to the demand for specific and sensitive analysis of hallucinogens in biological material is gas chromatography - mass spectrometry (GC-MS). Thus, at present, analysis of cannabinoids, tropane alkaloids, ketamine as well as psilocin (N,N-dimethyltryptamine derivative) is well-managed. CONCLUSIONS: The introduction of GC-MS systems appears to be indispensable for satisfactory qualitative and quantitative analysis of drugs of abuse, particularly hallucinogens in biological material.

Chromatography, Thin Layer↗
PubMed1996

LSD and the phenethylamine hallucinogen DOI are potent partial agonists at 5-HT2A receptors on interneurons in rat piriform cortex.

Correlations between 5-hydroxytryptamine (5-HT) receptor binding affinities and human hallucinogenic potency have suggested that 5-HT2 receptors mediate the hallucinogenic effects of lysergic acid diethylamide (LSD) and phenethylamine hallucinogens. Electrophysiological studies have suggested that a subpopulation of gamma-aminobutyric acid (GABA)ergic interneurons in layer III of the rat piriform cortex are excited by serotonin (5-HT) via 5-HT2A receptors. These interneurons have inhibitory inputs on pyramidal cells in layer II. In the present study, we tested low concentrations of both LSD (3-100 nM) and the phenethylamine hallucinogen 1-(2,5-dimethoxy-4-iodophenyl-2-aminopropane (DOI; 0.3-10 microM) on rat piriform cortical interneurons that were excited by 5-HT. Both LSD (3-100 nM) and DOI (0.3-10 microM) excited almost every cell excited by 5-HT. The maximal excitation achieved with LSD and DOI was 39% and 55% of the effect of a near-maximal 5-HT concentration (100 microM). Consistent with a partial agonist action, LSD and DOI blocked the 5-HT excitation of piriform cortical interneurons only at the higher hallucinogen concentrations tested. A specific 5-HT2A receptor antagonist, MDL 100,907, blocked excitation of these interneurons by 5-HT, LSD and DOI, but not by norepinephrine or alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionate. Again, consistent with a partial agonist action of the hallucinogens, intracellular experiments showed that a maximal concentration of DOI (10 microM) induced fewer postsynaptic inhibitory currents than did 5-HT (100 microM) in pyramidal neurons in layer II of the piriform cortex. Based on the present electrophysiological studies, we conclude that LSD and DOI, a phenethylamine hallucinogen, act as highly potent partial agonists at cortical 5-HT2A receptors.

Action Potentials↗