Human Brain Mapping
September 16, 2011
Dráulio Barros de Araújo, Sidarta Ribeiro, Guillermo Cecchi et al.
241 citations
Ayahuasca, a hallucinogenic brew containing serotonergic agonists and reuptake inhibitors, triggers vivid visual imagery during ceremonies. Using functional magnetic resonance imaging while participants performed a closed-eyes imagery task, the brew produced a robust increase in activation across occipital, temporal, and frontal brain areas. In the primary visual area, activation levels matched those of natural image viewing with eyes open. This effect correlated with individual perceptual changes measured by psychiatric scales. Activity in areas BA30 and BA37, linked to episodic memory and contextual associations, was also potentiated. Modulation of BA10, involved in prospective imagination and working memory, was detected. The findings suggest Ayahuasca seeings arise from an extensive network for vision, memory, and intention, lending a sense of reality to inner experiences.
Clinical Chemistry
January 23, 2009
Allan J. Barnes, Bruno Spinosa de Martinis, David A. Gorelick et al.
38 citations
In a controlled study, 15 healthy volunteers with prior MDMA use received placebo, low (1.0 mg/kg), and high (1.6 mg/kg) oral doses of MDMA in random order while wearing sweat patches for up to 7 days. MDMA was the main substance found in 59.7% of patches, with concentrations up to 3007 ng/patch; its metabolite MDA appeared in 29.4% of patches at lower levels, while other metabolites were undetected. At the 25-ng/patch threshold, 35% of patches were positive for MDMA. Sweat testing reliably detects MDMA use, but high variability in excretion means results should be interpreted qualitatively, not quantitatively.
Journal of Analytical Toxicology
January 21, 2020
Lidiane Silva Tavares, Fernanda Monedeiro, Dayanne Mozaner Bordin et al.
15 citations
Sweat can be used to detect the main active components of ayahuasca—harmine, harmaline, and N,N-dimethyltryptamine (DMT)—during religious rituals. A solid-phase extraction method under basic conditions showed high selectivity and extraction efficiency above 70%, with accuracy between 87.5 and 102.4% and precision below 10%. Detection limits were 15 ng/patch for harmine and harmaline and 10 ng/patch for DMT. Sweat offers a non-invasive, simple collection alternative that does not disrupt rituals, making it a viable matrix for monitoring ayahuasca use.
Journal of chromatography. A
August 16, 2024
Nayna Cândida Gomes, Oscar G Cabrices, Bruno Spinosa de Martinis
12 citations
A new method using disposable DPX-SCX extraction tips and gas chromatography-mass spectrometry can simultaneously detect and quantify 16 psychoactive substances—including amphetamines, cocaine, fentanyl, and several novel psychoactive substances—in sweat samples collected with laboratory-developed patches. Validation showed quantification limits between 2 and 30 ng per patch and linearity from 2 to 1100 ng per patch. When applied to 30 sweat samples from volunteer drug users, the method detected cocaine, MDMA, nicotine, caffeine, and other compounds, with recovery rates of 72.4% to 97.1%. Sweat is a viable, non-invasive biological matrix for monitoring drug use, particularly in rehabilitation settings.