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Experimental and Clinical Psychopharmacology

ISSN 1064-1297

8 papers in the library · 228 citations · publishing 2000-2023

Papers

Ethnoracial health disparities and the ethnopsychopharmacology of psychedelic-assisted psychotherapies.

Experimental and Clinical Psychopharmacology June 7, 2021 Colleen Fogg, Timothy I. Michaels, Sara de la Salle et al. 53 citations

Psychedelic-assisted psychotherapy (PAP) shows promise for treating substance use disorders, PTSD, depression, and anxiety in randomized, double-blind, placebo-controlled trials, but research has almost exclusively involved White populations in North America and Western Europe, neglecting Black, Indigenous, and People of Color (BIPOC). Ethnoracial differences in the metabolism, safety, and efficacy of psychotropic drugs are known from previous research, yet no studies have directly examined such differences for psychedelic pharmacology. This article argues that failing to include BIPOC in trials limits generalizability and overlooks biological and social factors affecting responses to PAP. It discusses limitations of ethnopsychopharmacology and advocates for expanded funding to address cultural, clinical, and public health needs.

A three-choice discrimination procedure dissociates the discriminative stimulus effects of d-amphetamine and (±)-MDMA in rats.

Experimental and Clinical Psychopharmacology January 1, 2000 A. K. Goodwin, L. E. Baker 44 citations

MDMA produces subjective effects in humans that are similar to, but distinguishable from, those of psychostimulants. In rats trained to discriminate between MDMA and d-amphetamine using a three-choice operant procedure, cocaine fully substituted for d-amphetamine, while LSD dose-dependently increased MDMA-appropriate responding, reaching nearly complete substitution (78%) for MDMA. The hallucinogen 2,5-dimethoxy-4-bromoamphetamine only partially substituted for MDMA and severely disrupted response rate. Fenfluramine and both isomers of MDA fully substituted for MDMA. The serotonin-receptor antagonist pirenpirone only partially blocked MDMA discrimination.

Effects of acute and repeated treatment with serotonin 5-HT2A receptor agonist hallucinogens on intracranial self-stimulation in rats.

Experimental and Clinical Psychopharmacology January 10, 2019 Farhana Sakloth, Elizabeth Leggett, Megan J. Moerke et al. 42 citations

The classic hallucinogens LSD, mescaline, and psilocybin, classified as Schedule 1 drugs, were tested in rats using intracranial self-stimulation (ICSS), a procedure that detects abuse-related effects of other drugs. In acute tests, all three drugs predominantly depressed ICSS, with weak and inconsistent evidence of abuse-related facilitation. Repeated LSD treatment did not alter its own depressant effects or the abuse-related effects of methamphetamine, but it did attenuate ICSS depression caused by the kappa opioid receptor agonist U69,593. These findings suggest that 5-HT2A agonist hallucinogens have weak abuse potential and provide evidence that repeated LSD may reduce depressant-like effects mediated by kappa opioid receptors.

In vivo pharmacology of MDMA and its enantiomers in rhesus monkeys.

Experimental and Clinical Psychopharmacology February 1, 2008 William E. Fantegrossi 30 citations

The chiral nature of the MDMA molecule produces two enantiomers, each biologically active. Reviewing the author's research and other publications, no differences between racemic MDMA and its enantiomers in maintaining behavior were noted. Blocking the 5-HT2A receptor shifted the dose-effect function rightward for S(+)-MDMA but insurmountably reduced the reinforcing effects of R(-)-MDMA. Long-term self-administration can lead to chronic tolerance, with S(+)-MDMA somewhat less susceptible than the racemate or R(-)-enantiomer. PET neuroimaging showed negligible dopamine transporter occupancy after R(-)-MDMA but reasonable interaction after S(+)-MDMA. Non-human primate studies caution that results with enantiomers may not inform about the racemate and vice versa.

Call for evidence-based psychedelic integration.

Experimental and Clinical Psychopharmacology November 27, 2023 Jakub Greń, Ingmar Gorman, Anastasia Ruban et al. 27 citations

Psychedelic integration (PI) refers to practices that aim to minimize harms or maximize benefits after psychedelic use. Although PI is considered essential in psychedelic-assisted therapy, existing models lack empirical support and are not evidence-based. With psychedelic use increasing, the article calls for scientific efforts to develop, examine, and evaluate PI methods. It summarizes current literature, suggests research avenues, and discusses limitations and challenges of PI-focused research.

Syllogistic Reasoning Performance in MDMA (Ecstasy) Users.

Experimental and Clinical Psychopharmacology January 1, 2005 Catharine Montgomery, John E. Fisk, Russell Newcombe et al. 22 citations

Recreational use of MDMA (Ecstasy) is linked to impairments in syllogistic reasoning, a form of logical deduction. In a study comparing 22 MDMA users (average age 21.36) with 26 non-users (average age 21.31), users performed significantly worse on reasoning tasks, even after accounting for other drug use. However, this deficit was no longer statistically significant when differences in working memory capacity were considered. The findings suggest that MDMA-related declines in working memory and executive function may underlie the observed reasoning difficulties.

Harmine impairs memory performance of treated rats and nontreated cagemates.

Experimental and Clinical Psychopharmacology November 4, 2021 Tânia Cristina Libânio, R. Eufrásio, Suzy S Niigaki et al. 6 citations

Harmine, a component of the psychedelic brew ayahuasca, impairs memory in emotional contexts in rats, and even untreated rats housed with harmine-treated rats show memory deficits. In experiments using contextual and tone fear conditioning and a plus-maze discriminative avoidance task, harmine at 10 mg/kg impaired contextual fear conditioning, and all doses (5, 10, or 15 mg/kg) impaired discriminative avoidance. Untreated rats housed in cages with harmine-treated rats also showed memory deficits across all tasks, suggesting that social context and cohabitation can influence the drug's behavioral effects.

To treat or not to treat? High-potency benzodiazepine use in a case of comorbid hallucinogen persisting perception disorder and alcohol use disorder.

Experimental and Clinical Psychopharmacology September 1, 2022 Julie A. Christensen, David C. Fipps, J Michael Bostwick 4 citations

Hallucinogen persisting perception disorder (HPPD) causes visual disturbances that resemble psychedelic intoxication and persist after drug use stops. A 37-year-old man with a history of alcohol, cannabis, LSD, cocaine, and nicotine use disorders experienced visual distortions—such as halos around objects, moving walls, and cartoonish figures—for over 20 years after his last LSD use. He understood these perceptions were not real. Hospital tests, including head CT and EEG, found no other cause. His symptoms resolved with scheduled clonazepam treatment, though treatment programs were hesitant to accept him while on a benzodiazepine. The case highlights the need to distinguish HPPD from psychosis and to weigh risks and benefits of long-term benzodiazepine use for patients with co-occurring substance use disorders.