Journal of Psychopharmacology
August 31, 2016
Theresa M. Carbonaro, Matthew P. Bradstreet, Frederick S. Barrett et al.
541 citations
In a survey of 1,993 people who recalled their worst 'bad trip' after taking psilocybin mushrooms, 39% ranked it among the top five most challenging experiences of their lives. Eleven percent put themselves or others at risk of physical harm, with factors such as higher dose, longer duration, and lack of physical comfort or social support increasing that risk. About 2.6% acted aggressively and 2.7% needed medical help. Among those whose experience was more than a year prior, 7.6% sought treatment for lasting psychological symptoms, with three cases linked to enduring psychotic symptoms and three to attempted suicide. Despite difficulties, 84% reported benefiting from the experience. The incidence of risky behavior or lasting distress is very low when psilocybin is given in controlled laboratory settings.
Brain Research Bulletin
April 30, 2016
Theresa M. Carbonaro, Michael B. Gatch
258 citations
N,N-dimethyltryptamine (DMT) is an indole alkaloid found in plants and animals, known for producing brief, intense psychedelic effects. Evidence suggests endogenous DMT may act as a neurotransmitter in the periphery and central nervous system. This review covers recreational use, potential endogenous roles, pharmacokinetics, mechanisms of action, clinical uses, and adverse effects. DMT appears to have limited neurotoxicity and few adverse effects, except for intense cardiovascular effects when given intravenously in large doses. It may be a useful experimental tool for exploring brain function and a clinical tool for treating anxiety and psychosis.
Journal of Psychopharmacology
February 20, 2021
Albert Garcia‐romeu, Frederick S. Barrett, Theresa M. Carbonaro et al.
101 citations
Psilocybin, a naturally occurring psychedelic, shows promise for treating mood and substance use disorders when given in structured settings. Most trials have adjusted the dose by body weight, but fixed dosing is simpler and cheaper. Analyzing data from ten previous studies (total 288 participants) that used weight-adjusted doses of 20 or 30 mg per 70 kg, or a fixed dose approximating 25 mg, no significant associations emerged between body weight or sex and the subjective effects (mystical, challenging, or intensity). Across body weights from 49 to 113 kg, body weight did not affect psilocybin's subjective effects, suggesting fixed dosing is as effective and more practical than weight-adjusted dosing.
Psychopharmacology
July 2, 2014
Theresa M. Carbonaro, Amy J. Eshleman, Michael J. Forster et al.
67 citations
The 5-HT2A receptor plays a major role in mediating the effects of the hallucinogens DMT and DiPT. A 5-HT2A receptor inverse agonist fully blocked the discriminative stimulus effects of DMT but only partially blocked those of DiPT. A 5-HT2C receptor antagonist partially attenuated DiPT's effects but minimally affected DMT. An mGluR2/3 agonist produced potent but partial blockade of DMT's effects, while an mGluR2/3 antagonist facilitated the effects of both compounds. Both DMT and DiPT induced head twitches, with DiPT producing more, and these were blocked by a 5-HT2A receptor inverse agonist. DiPT acted as a low-potency full agonist at the 5-HT2C receptor in vitro. The findings suggest that 5-HT2C and mGluR2 receptors modulate the effects of these tryptamine hallucinogens to some degree.
Frontiers in Neuroergonomics
January 20, 2022
Yun Zhou, Frederick S. Barrett, Theresa M. Carbonaro et al.
17 citations
A psychoactive dose of psilocybin (10 mg/70 kg) occupied an average of 39.5% of serotonin 2A receptors in the brains of four healthy volunteers, as measured by PET imaging. The highest occupancy occurred in regions of the default mode network, including the subgenual anterior cingulate and bilateral angular gyri, with values between 63.12% and 74.72%. Individual variability in regional occupancy was marked. These findings support further research into how differences in receptor occupancy relate to psilocybin's acute and lasting effects.
ACS Pharmacology & Translational Science
December 29, 2020
Michael B. Gatch, Adam C. Hoch, Theresa M. Carbonaro
13 citations
Eight novel substituted tryptamines produced hallucinogen-like effects in rats trained to discriminate the hallucinogen DOM from saline. All compounds fully substituted for DOM, with potencies equal to or less than DOM. Four compounds—4-OH-MET, 4-OH-DET, 4-OH-DMT, and 4-AcO-DMT—reduced response rates at fully substituting doses. Because these compounds mimic DOM's discriminative stimulus effects, they may carry similar abuse liability. 4-Acetoxy substituted compounds were less potent than 4-hydroxy ones, and N,N-diisopropyl compounds were less potent than those with dimethyl, diethyl, N-methyl-N-ethyl, or N-methyl-N-isopropyl groups.
Drug and Alcohol Dependence
January 21, 2017
Theresa M. Carbonaro, Matthew W. Johnson, Roland R. Griffiths
3 citations
No Summary
Drug and Alcohol Dependence
December 16, 2014
Theresa M. Carbonaro, Frederick S. Barrett, Matthew P. Bradstreet et al.
3 citations
No Summary
Drug and Alcohol Dependence
October 31, 2015
Theresa M. Carbonaro, Margaret Klinedinst, Matthew W. Johnson et al.
1 citation
No Summary