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Kelan Thomas

Clinical Sciences, Touro University California College of Pharmacy, Vallejo, CA, USA. kthomas10@touro.edu.

5 papers in the library · 200 citations · publishing 2017-2025

Papers

Drug-drug interactions between psychiatric medications and MDMA or psilocybin: a systematic review

Psychopharmacology March 7, 2022 Aryan Sarparast, Kelan Thomas, Benjamin Malcolm et al. 85 citations

As MDMA and psilocybin progress through FDA drug development, this systematic review compiles existing research on psychiatric drug-drug interactions with these substances. It identifies which medications may alter the effects or safety of MDMA- and psilocybin-assisted therapy, providing a resource for clinicians and researchers. The review suggests that certain psychiatric drugs, such as SSRIs and other serotonergic agents, can diminish or alter the subjective and physiological responses to MDMA and psilocybin, while others may increase risks. The authors indicate that careful medication management is necessary during psychedelic-assisted therapy to optimize outcomes and minimize adverse events.

Psilocybin-Assisted Therapy: A Review of a Novel Treatment for Psychiatric Disorders

Journal of Psychoactive Drugs May 8, 2017 Kelan Thomas, Benjamin Malcolm, Dan Lastra 77 citations

A review of seven clinical trials found that psilocybin-assisted therapy reduced symptoms of anxiety, depression, and substance use, with large effect sizes for improved depression and anxiety. Reductions in alcohol or tobacco use and increased abstinence rates in addiction were less clear due to open-label designs without statistical analysis. The therapy appears promising, but more robust trials are needed for FDA approval.

Concomitant drugs associated with increased mortality for MDMA users reported in a drug safety surveillance database

Scientific Reports March 16, 2021 Isaac Cohen, Tigran Makunts, Ruben Abagyan et al. 30 citations

Using FDA drug safety surveillance data, nearly one thousand reports of MDMA use were analyzed to evaluate risks of death when MDMA is taken alone or with other medications. Several drug classes—including MDMA metabolites or analogs, anesthetics, muscle relaxants, amphetamines and stimulants, benzodiazepines, ethanol, and opioids—along with the antidepressants bupropion, sertraline, venlafaxine, and citalopram, and the antipsychotic olanzapine, showed increased odds ratios for reported risk of death. The authors call for future clinical trials to assess whether these drug–drug interactions pose actual harm in controlled medical settings.

Concomitant use of antidepressants and classic psychedelics: A scoping review

Journal of Psychopharmacology September 12, 2025 Stephan Tap, Kelan Thomas, Tomáš Páleníček et al. 5 citations

Classic psychedelics like psilocybin are being studied for psychiatric disorders. Current protocols typically require patients to stop antidepressants (ADs) for at least two weeks before psychedelic use to avoid serotonin syndrome and preserve efficacy, but discontinuation can worsen depression and increase suicidal ideation. This scoping review of 18 studies found that using ADs alongside classic psychedelics is generally safe and tolerable, with no increased risk of serotonin syndrome, especially with psilocybin. Some studies showed significant improvements in depression and other symptoms. Although some evidence suggests a potential reduction in acute subjective psychedelic effects, this was not consistent. The authors conclude that maintaining ADs may improve patient access and avoid discontinuation risks.

Toxicology and Pharmacological Interactions of Classic Psychedelics.

Current topics in behavioral neurosciences July 24, 2024 Kelan Thomas 3 citations

As psychedelics are studied for more medical uses, understanding their adverse effects and interactions with other drugs is increasingly important. This chapter reviews the known toxicology and drug-drug interactions of classic psychedelics, including LSD, psilocybin, DMT, 5-MeO-DMT, mescaline, 2C-B, Bromo-DragonFLY, and 25X-NBOMe.