Neural and subjective effects of inhaled N,N-dimethyltryptamine in natural settings.

BACKGROUND: N,N-dimethyltryptamine is a short-acting psychedelic tryptamine found naturally in many plants and animals. Few studies to date have addressed the neural and psychological effects of N,N-dimethyltryptamine alone, either administered intravenously or inhaled in freebase form, and none have been conducted in natural settings. AIMS: Our primary aim was to study the acute effects of inhaled N,N-dimethyltryptamine in natural settings, focusing on questions tuned to the advantages of conducting field research, including the effects of contextual factors (i.e. "set" and "setting"), the possibility of studying a comparatively large number of subjects, and the relaxed mental state of participants consuming N,N-dimethyltryptamine in familiar and comfortable settings. METHODS: We combined state-of-the-art wireless electroencephalography with psychometric questionnaires to study the neural and subjective effects of naturalistic N,N-dimethyltryptamine use in 35 healthy and experienced participants. RESULTS: We observed that N,N-dimethyltryptamine significantly decreased the power of alpha (8-12 Hz) oscillations throughout all scalp locations, while simultaneously increasing power of delta (1-4 Hz) and gamma (30-40 Hz) oscillations. Gamma power increases correlated with subjective reports indicative of some features of mystical-type experiences. N,N-dimethyltryptamine also increased global synchrony and metastability in the gamma band while decreasing those measures in the alpha band. CONCLUSIONS: Our results are consistent with previous studies of psychedelic action in the human brain, while at the same time the results suggest potential electroencephalography markers of mystical-type experiences in natural settings, thus highlighting the importance of investigating these compounds in the contexts where they are naturally consumed.

Epidemiología de las intoxicaciones agudas por drogas de abuso en las urgencias de un hospital del Centro de España basada en datos de análisis toxicológico de orina / Epidemiology of acute poisonings for drugs of abuse in the emergency room of a hospital from the Center of Spain based on analysis data toxicological urine

Introducción: las intoxicaciones agudas son motivo de consulta cada vez más frecuente en los Servicios de Urgencia hospitalarios (SUH) debido a la mayor disponibilidad y acceso a productos químicos tóxicos. Se observan diferentes patrones en cada área sanitaria según el tipo de población, geografía y perfil epidemiológico de consumo. Material y métodos: el objetivo de nuestro estudio es realizar un perfil epidemiológico y describir el manejo del paciente que acude por clínica compatible con intoxicación aguda por drogas de abuso (IA) basado en la determinación de tóxicos en orina para seis sustancias (cannabis, opiáceos, cocaína, anfetaminas, benzodiazepinas y éxtasis) solicitados en el período de estudio 2010-2012. Resultados: se solicitaron 2755 peticiones, de las cuales fueron positivas 1429, y se estudiaron al azar 661 historias clínicas. El perfil de paciente intoxicado de nuestra área es el de varón de entre 30 y 40 años, consumidor preferentemente de cannabis y cocaína; las benzodiazepinas son el tóxico más frecuente en las mujeres, con clínica mayoritariamente neurológica, sin diferencias en cuanto a la franja horaria o el mes del año en que recibió el alta desde el propio SUH en casi el 60% de los casos. Discusión: las IA en los SUH representan casi el 1% de las consultas y tienen una escasa mortalidad. En algunos casos, el médico de urgencias comienza el tratamiento antes de conocer el resultado toxicológico, lo que nos hace plantearnos la utilidad real y el coste-efectividad de estas determinaciones en todos los pacientes con alteración del nivel de conciencia. (AU)

Introduction: acute intoxications are a rising and common query demand on the emergency rooms because of the easy access and disponibility to toxic substances, where we can observe different patterns attending to type of population, geography and epidemiologic consume profile. Material and methods: our objective is to analyze the epidemiology and patient handling coming to the Emergency Room (ER) with compatible symptoms of street drugs abuse, based on the determination of cannabis, cocaine, amphetamine, benzodiazepine, opiates and ectasy urine levels in the period 2010-2012. Results: the ER requested 2755 determinations being positive 1429 and randomly examined 661 clinical histories. The profile of intoxicated patient was male, 30 to 40 years old, preferently cannabis and cocaine consumer (benzodiazepine in women), mostly with neurological symptoms when arrive, without differences between months or day time and, almost 60% of them, discharged directly from the ER. Conclusions: acute intoxications barely represent 1% of ER demands and produce poor or scarce mortality. Sometimes, doctors in charge start with therapeutic measures before knowing the results of toxicology, what leads us to ask about actual usefulness and cost-efficiency of the toxicology assay to every patient with low conscious level. (AU)

The psychedelic state induced by ayahuasca modulates the activity and connectivity of the default mode network.

The experiences induced by psychedelics share a wide variety of subjective features, related to the complex changes in perception and cognition induced by this class of drugs. A remarkable increase in introspection is at the core of these altered states of consciousness. Self-oriented mental activity has been consistently linked to the Default Mode Network (DMN), a set of brain regions more active during rest than during the execution of a goal-directed task. Here we used fMRI technique to inspect the DMN during the psychedelic state induced by Ayahuasca in ten experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians composed by a mixture of compounds that increase monoaminergic transmission. In particular, we examined whether Ayahuasca changes the activity and connectivity of the DMN and the connection between the DMN and the task-positive network (TPN). Ayahuasca caused a significant decrease in activity through most parts of the DMN, including its most consistent hubs: the Posterior Cingulate Cortex (PCC)/Precuneus and the medial Prefrontal Cortex (mPFC). Functional connectivity within the PCC/Precuneus decreased after Ayahuasca intake. No significant change was observed in the DMN-TPN orthogonality. Altogether, our results support the notion that the altered state of consciousness induced by Ayahuasca, like those induced by psilocybin (another serotonergic psychedelic), meditation and sleep, is linked to the modulation of the activity and the connectivity of the DMN.

Neonatal benzodiazepines exposure during breastfeeding.

OBJECTIVE: To assess central nervous system depression and other adverse effects in infants exposed to benzodiazepines through breast milk. STUDY DESIGN: A prospectively recruited, retrospectively assessed cohort study of mothers who contacted the Motherisk program regarding the safety of benzodiazepines and were invited to participate in a follow-up program regarding the effects of these medications on their infants during lactation. RESULTS: A total of 124 consenting women participated. Adverse outcomes, specifically sedation, was identified in only 1.6% (2 of 124) of infants and was not associated with benzodiazepine dose, number of hours breastfed, or any demographic trait. Mothers reporting adverse outcomes in themselves (26% [32 of 124]) were more likely to be taking concomitantly a greater number of central nervous system depressants. CONCLUSIONS: This study supports the continued recommendation to initiate breastfeeding while taking benzodiazepines postpartum.

Alcaloides e o chá de ayahuasca: uma correlação dos "estados alterados da consciência" induzido por alucinógenos / Alkaloids and ayahuasca tea: a correlation of hallucinogen-induced "altered states of consciousness"

Dentre as inúmeras plantas alucinógenas utilizadas por populações indígenas da bacia amazônica, talvez nenhuma delas seja mais interessante ou complexa em termos botânicos, químicos ou etnográficos, como a bebida alucinógena conhecida como ayahuasca, hoasca, medicina, vegetal ou daime. Ayahuasca é bebida psicotrópica da América do Sul de destacado uso no xamanismo de muitas tribos indígenas da Amazônia, obtida pela fervura da casca do cipó de Banisteriopis caapi com a mistura de folhas de Psycotria, principalmente P. viridis. No Brasil, ocupa posição de destaque na etnomedicina. A natureza química dos compostos ativos, bem como, a maneira de utilização faz com que essa bebida ocupe posição de destaque nos atuais estudos da neurofarmacologia, neurofisiologia e psiquiatria. Alucinógenos e substâncias relacionadas constituem poderosa base experimental para investigar a correlação biológica dos estados alterados de consciência. O estudo de alucinógenos em humanos é de suma importância porque as substâncias com essas propriedades afetam certas funções cerebrais que tipicamente caracterizam a mente humana, incluindo a cognição, volição, ego e auto-percepção. As várias manifestações dos "desequilíbrios do ego" são especialmente características psicodélicas proeminentes, que acabam naturalmente criando psicoses. Sumarizamos nessa revisão alguns aspectos importantes no estudo do chá de ayahuasca em humanos, as indicações e contra-indicações para fins terapêuticos e religiosos.

Among the numerous hallucinogenic plants utilized by indigenous populations of the Amazon Basin, perhaps none is as interesting or complex in terms of botany, chemistry or ethnography as the hallucinogenic beverage known as ayahuasca, hoasca, medicine, vegetable or daime. Ayahuasca is a South American psychotropic beverage that is prominent in the shamanism of many indigenous Amazonian tribes and is obtained by boiling the bark of the liana Banisteriopsis caapi together with the mixture of leaves of Psychotria, principally P. viridis. In Brazil, it occupies a central position in ethnomedicine. The chemical nature of its active constituents and the manner of its use makes it relevant to contemporary studies in neuropharmacology, neurophysiology, and psychiatry. Hallucinogens and related substances constitute a powerful experimental basis to investigate the biological correlation of altered states of consciousness. The study of hallucinogens in humans is important because these substances affect a number of brain functions that typically characterize the human mind, including cognition, volition, ego, and self-consciousness. The several manifestations of "ego disorders" are especially prominent psychedelic features that naturally lead to psychoses. In the present review, we summarize some of the important aspects in the study of ayahuasca tea in humans, its indications and contraindications for therapeutic and religious purposes.

[Star fruit (Averrhoa carambola) toxic encephalopathy]. / Encéphalopathie toxique par ingestion de carambole (Averrhoa carambola).

Ingestion of star fruit (Averrhoa carambola) can induce severe intoxication in subjects with chronic renal failure. Oxalate plays a key role in the neurotoxicity of star fruit. We report the cases of two patients with unknown chronic renal insufficiency who developed severe encephalopathy after ingestion of star fruit. The two patients developed intractable hiccups, vomiting, impaired consciousness and status epilepticus. Diffusion-weighted MR imaging showed cortical and thalamic hyperintense lesions related to epileptic status. They improved after being submitted to continuous hemofiltration which constitutes the most effective treatment during the acute phase.