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Racemic 3,4-methylenedioxymethamphetamine (MDMA) acutely increases mood, feelings of empathy, trust, and closeness to others and is investigated to assist psychotherapy. Preclinical research indicates that S-MDMA releases monoamines and oxytocin more potently than R-MDMA, whereas R-MDMA more potently stimulates serotonin 5-hydroxytryptamine-2A receptors. S-MDMA may have more stimulant properties, and R-MDMA may be more psychedelic-like. However, acute effects of S- and R-MDMA have not been examined in a controlled human study. We used a double-blind, randomized, placebo-controlled, crossover design to compare acute effects of MDMA (125 mg), S-MDMA (125 mg), R-MDMA (125 mg and 250 mg), and placebo in 24 healthy participants. Outcome measures included subjective, autonomic, and adverse effects, pharmacokinetics, and plasma oxytocin, prolactin, and cortisol concentrations. S-MDMA (125 mg) induced greater subjective effects ("stimulation," "drug high," "happy," "open") and higher increases in blood pressure than R-MDMA (both 125 and 250 mg) and MDMA (125 mg). Unexpectedly, R-MDMA did not produce more psychedelic-like effects than S-MDMA. S-MDMA increased plasma prolactin more than MDMA, and S-MDMA increased plasma cortisol and oxytocin more than MDMA and R-MDMA. The plasma elimination half-life of S-MDMA was 4.1 h after administration. The half-life of R-MDMA was 12 and 14 h after the administration of 125 and 250 mg, respectively. Half-lives for S-MDMA and R-MDMA were 5.1 h and 11 h, respectively, after racemic MDMA administration. Concentrations of the CYP2D6-formed MDMA-metabolite 4-hydroxy-3-methoxymethamphetamine were lower after R-MDMA administration compared with S-MDMA administration. The pharmacokinetic findings are consistent with the R-MDMA-mediated inhibition of CYP2D6. Stronger stimulant-like effects of S-MDMA in the present study may reflect the higher potency of S-MDMA rather than qualitative differences between S-MDMA and R-MDMA. Equivalent acute effects of S-MDMA, MDMA, and R-MDMA can be expected at doses of 100, 125, and 300 mg, respectively, and need to be investigated.Trial registration: ClinicalTrials.gov identifier: NCT05277636.
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N,N-dimethyltryptamine (DMT) is distinct among classic serotonergic psychedelics because of its short-lasting effects when administered intravenously. Despite growing interest in the experimental and therapeutic use of intravenous DMT, data are lacking on its clinical pharmacology. We conducted a double-blind, randomized, placebo-controlled crossover trial in 27 healthy participants to test different intravenous DMT administration regimens: placebo, low infusion (0.6 mg/min), high infusion (1 mg/min), low bolus + low infusion (15 mg + 0.6 mg/min), and high bolus + high infusion (25 mg + 1 mg/min). Study sessions lasted for 5 h and were separated by at least 1 week. Participant's lifetime use of psychedelics was ≤20 times. Outcome measures included subjective, autonomic, and adverse effects, pharmacokinetics of DMT, and plasma levels of brain-derived neurotropic factor (BDNF) and oxytocin. Low (15 mg) and high (25 mg) DMT bolus doses rapidly induced very intense psychedelic effects that peaked within 2 min. DMT infusions (0.6 or 1 mg/min) without a bolus induced slowly increasing and dose-dependent psychedelic effects that reached plateaus after 30 min. Both bolus doses produced more negative subjective effects and anxiety than infusions. After stopping the infusion, all drug effects rapidly decreased and completely subsided within 15 min, consistent with a short early plasma elimination half-life (t1/2α) of 5.0-5.8 min, followed by longer late elimination (t1/2ß = 14-16 min) after 15-20 min. Subjective effects of DMT were stable from 30 to 90 min, despite further increasing plasma concentrations, thus indicating acute tolerance to continuous DMT administration. Intravenous DMT, particularly when administered as an infusion, is a promising tool for the controlled induction of a psychedelic state that can be tailored to the specific needs of patients and therapeutic sessions.Trial registration: ClinicalTrials.gov identifier: NCT04353024.
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Alucinógenos , N,N-Dimetiltriptamina , Humanos , Voluntários Saudáveis , Administração Intravenosa , AnsiedadeRESUMO
Mescaline, lysergic acid diethylamide (LSD), and psilocybin are classic serotonergic psychedelics. A valid, direct comparison of the effects of these substances is lacking. The main goal of the present study was to investigate potential pharmacological, physiological and phenomenological differences at psychoactive-equivalent doses of mescaline, LSD, and psilocybin. The present study used a randomized, double-blind, placebo-controlled, cross-over design to compare the acute subjective effects, autonomic effects, and pharmacokinetics of typically used, moderate to high doses of mescaline (300 and 500 mg), LSD (100 µg), and psilocybin (20 mg) in 32 healthy participants. A mescaline dose of 300 mg was used in the first 16 participants and 500 mg was used in the subsequent 16 participants. Acute subjective effects of 500 mg mescaline, LSD, and psilocybin were comparable across various psychometric scales. Autonomic effects of 500 mg mescaline, LSD, and psilocybin were moderate, with psilocybin causing a higher increase in diastolic blood pressure compared with LSD, and LSD showing a trend toward an increase in heart rate compared with psilocybin. The tolerability of mescaline, LSD, and psilocybin was comparable, with mescaline at both doses inducing slightly more subacute adverse effects (12-24 h) than LSD and psilocybin. Clear distinctions were seen in the duration of action between the three substances. Mescaline had the longest effect duration (mean: 11.1 h), followed by LSD (mean: 8.2 h), and psilocybin (mean: 4.9 h). Plasma elimination half-lives of mescaline and LSD were similar (approximately 3.5 h). The longer effect duration of mescaline compared with LSD was due to the longer time to reach maximal plasma concentrations and related peak effects. Mescaline and LSD, but not psilocybin, enhanced circulating oxytocin. None of the substances altered plasma brain-derived neurotrophic factor concentrations. In conclusion, the present study found no evidence of qualitative differences in altered states of consciousness that were induced by equally strong doses of mescaline, LSD, and psilocybin. The results indicate that any differences in the pharmacological profiles of mescaline, LSD, and psilocybin do not translate into relevant differences in the subjective experience. ClinicalTrials.gov identifier: NCT04227756.
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Alucinógenos , Psilocibina , Humanos , Psilocibina/farmacologia , Mescalina/farmacologia , Dietilamida do Ácido Lisérgico/farmacologia , Estudos Cross-Over , Voluntários Saudáveis , Alucinógenos/farmacologiaRESUMO
INTRODUCTION: The real-life short-term implications of electromagnetic fields (RF-EMF) on cognitive performance and health-related quality of life have not been well studied. The SPUTNIC study (Study Panel on Upcoming Technologies to study Non-Ionizing radiation and Cognition) aimed to investigate possible correlations between mobile phone radiation and human health, including cognition, health-related quality of life and sleep. METHODS: Adult participants tracked various daily markers of RF-EMF exposures (cordless calls, mobile calls, and mobile screen time 4 h prior to each assessment) as well as three health outcomes over ten study days: 1) cognitive performance, 2) health-related quality of life (HRQoL), and 3) sleep duration and quality. Cognitive performance was measured through six "game-like" tests, assessing verbal and visuo-spatial performance repeatedly. HRQoL was assessed as fatigue, mood and stress on a Likert-scale (1-10). Sleep duration and efficiency was measured using activity trackers. We fitted mixed models with random intercepts per participant on cognitive, HRQoL and sleep scores. Possible time-varying confounders were assessed at daily intervals by questionnaire and used for model adjustment. RESULTS: A total of 121 participants ultimately took part in the SPUTNIC study, including 63 from Besancon and 58 from Basel. Self-reported wireless phone use and screen time were sporadically associated with visuo-spatial and verbal cognitive performance, compatible with chance findings. We found a small but robust significant increase in stress 0.03 (0.00-0.06; on a 1-10 Likert-scale) in relation to a 10-min increase in mobile phone screen time. Sleep duration and quality were not associated with either cordless or mobile phone calls, or with screen time. DISCUSSION: The study did not find associations between short-term RF-EMF markers and cognitive performance, HRQoL, or sleep duration and quality. The most consistent finding was increased stress in relation to more screen time, but no association with cordless or mobile phone call time.
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Exposição Ambiental , Qualidade de Vida , Adulto , Humanos , Telefone , Cognição , SonoRESUMO
There is renewed interest in the use of lysergic acid diethylamide (LSD) in psychiatric research and practice. Although acute subjective effects of LSD are mostly positive, negative subjective effects, including anxiety, may occur. The induction of overall positive acute subjective effects is desired in psychedelic-assisted therapy because positive acute experiences are associated with greater therapeutic long-term benefits. 3,4-Methylenedioxymethamphetamine (MDMA) produces marked positive subjective effects and is used recreationally with LSD, known as "candyflipping." The present study investigated whether the co-administration of MDMA can be used to augment acute subjective effects of LSD. We used a double-blind, randomized, placebo-controlled, crossover design with 24 healthy subjects (12 women, 12 men) to compare the co-administration of MDMA (100 mg) and LSD (100 µg) with MDMA and LSD administration alone and placebo. Outcome measures included subjective, autonomic, and endocrine effects and pharmacokinetics. MDMA co-administration with LSD did not change the quality of acute subjective effects compared with LSD alone. However, acute subjective effects lasted longer after LSD + MDMA co-administration compared with LSD and MDMA alone, consistent with higher plasma concentrations of LSD (Cmax and area under the curve) and a longer plasma elimination half-life of LSD when MDMA was co-administered. The LSD + MDMA combination increased blood pressure, heart rate, and pupil size more than LSD alone. Both MDMA alone and the LSD + MDMA combination increased oxytocin levels more than LSD alone. Overall, the co-administration of MDMA (100 mg) did not improve acute effects or the safety profile of LSD (100 µg). The combined use of MDMA and LSD is unlikely to provide relevant benefits over LSD alone in psychedelic-assisted therapy. Trial registration: ClinicalTrials.gov identifier: NCT04516902.
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Alucinógenos , N-Metil-3,4-Metilenodioxianfetamina , Masculino , Humanos , Feminino , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Alucinógenos/farmacologia , Voluntários Saudáveis , Dietilamida do Ácido Lisérgico/farmacologia , Método Duplo-Cego , Estudos Cross-OverRESUMO
BACKGROUND: Lysergic acid diethylamide (LSD) is currently being investigated in psychedelic-assisted therapy. LSD has a long duration of acute action of 8-11 hours. It produces its acute psychedelic effects via stimulation of the serotonin 5-hydroxytryptamine-2A (HT2A) receptor. Administration of the 5-HT2A antagonist ketanserin before LSD almost fully blocks the acute subjective response to LSD. However, unclear is whether ketanserin can also reverse the effects of LSD when administered after LSD. METHODS: We used a double-blind, randomized, placebo-controlled, crossover design in 24 healthy participants who underwent two 14-hour sessions and received ketanserin (40 mg p.o.) or placebo 1 hour after LSD (100 µg p.o.). Outcome measures included subjective effects, autonomic effects, acute adverse effects, plasma brain-derived neurotrophic factor levels, and pharmacokinetics up to 12 hours. RESULTS: Ketanserin reversed the acute response to LSD, thereby significantly reducing the duration of subjective effects from 8.5 hours with placebo to 3.5 hours. Ketanserin also reversed LSD-induced alterations of mind, including visual and acoustic alterations and ego dissolution. Ketanserin reduced adverse cardiovascular effects and mydriasis that were associated with LSD but had no effects on elevations of brain-derived neurotrophic factor levels. Ketanserin did not alter the pharmacokinetics of LSD. CONCLUSIONS: These findings are consistent with an interaction between ketanserin and LSD and the view that LSD produces its psychedelic effects only when occupying 5-HT2A receptors. Ketanserin can effectively be used as a planned or rescue option to shorten and attenuate the LSD experience in humans in research and LSD-assisted therapy. TRIAL REGISTRY: ClinicalTrials.gov (NCT04558294).
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Alucinógenos , Humanos , Ketanserina/farmacologia , Alucinógenos/farmacologia , Dietilamida do Ácido Lisérgico/farmacologia , Estudos Cross-Over , Fator Neurotrófico Derivado do Encéfalo , Voluntários Saudáveis , Método Duplo-CegoRESUMO
Mescaline is a psychedelic phenethylamine found in different species of cacti. Currently, mescaline's acute subjective effects and pharmacokinetics are investigated in several modern clinical studies. Therefore, we developed a bioanalytical method for the rapid quantification of mescaline and its metabolites in human plasma. Mescaline and its metabolites 3,4,5-trimethoxyphenylacetic acid (TMPAA), N-acetyl mescaline (NAM), and 3,5-dimethoxy-4-hydroxyphenethylamine (4-desmethyl mescaline) were simultaneously analyzed by ultra-high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). Optimal chromatographic separation was achieved with an Acquity Premier HSS T3 C18 column. The analytes were detected in positive ionization mode using scheduled multiple reaction monitoring. A single step extraction method was implemented to enable fast and automatable plasma sample preparation. An intra-assay accuracy between 84.9% and 106% and a precision of ≤ 7.33% was observed in three validation runs. Plasma was extracted by simple protein precipitation, resulting in a complete recovery (≥ 98.3%) and minor matrix effects (≤ 7.58%). No interference with endogenous matrix components could be detected in human plasma samples (n = 7). Importantly, method sensitivity sufficed for assessing pharmacokinetic parameters of mescaline in clinical study samples with lower limits of quantification of 12.5, 12.5, and 1.25 ng/mL for mescaline, TMPAA, and NAM, respectively. Nonetheless, 4-desmethyl mescaline could not be selectively quantified in pharmacokinetic samples due to interference with another mescaline metabolite. Overall, we developed and validated a reliable and very easy-to-use method for forensic applications as well as investigating the clinical pharmacokinetics of mescaline.
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Alucinógenos , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Humanos , Mescalina , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , TiraminaRESUMO
The psychedelic psilocybin is being investigated for the treatment of depression and anxiety. Unclear is whether antidepressant treatments interact with psilocybin. The present study used a double-blind, placebo-controlled, crossover design with two experimental test sessions to investigate the response to psilocybin (25 mg) in healthy subjects after pretreatment with escitalopram or placebo. The treatment order was random and counterbalanced. Pretreatment consisted of 10 mg escitalopram daily for 7 days, followed by 20 mg daily for 7 days, including the day of psilocybin administration, or 14 days of placebo pretreatment before psilocybin administration. Psilocybin treatments were separated by at least 16 days. The outcome measures included self-rating scales that evaluated subjective effects, autonomic effects, adverse effects, plasma brain-derived neurotrophic factor (BDNF) levels, electrocardiogram QTc time, whole-blood HTR2A and SCL6A4 gene expression, and pharmacokinetics. Escitalopram pretreatment had no relevant effect on positive mood effects of psilocybin but significantly reduced bad drug effects, anxiety, adverse cardiovascular effects, and other adverse effects of psilocybin compared with placebo pretreatment. Escitalopram did not alter the pharmacokinetics of psilocin. The half-life of psychoactive free (unconjugated) psilocin was 1.8 hours (range 1.1-2.2 hours), consistent with the short duration of action of psilocybin. Escitalopram did not alter HTR2A or SCL6A4 gene expression before psilocybin administration, QTc intervals, or circulating BDNF levels before or after psilocybin administration. Further studies are needed with a longer antidepressant pretreatment time and patients with psychiatric disorders to further define interactions between antidepressants and psilocybin.