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Esther Papaseit

Clinical Pharmacology Department, Hospital Universitari Germans Trias i Pujol, Badalona, Spain.

10 papers in the library · 231 citations · publishing 2018-2025

Papers

Acute Pharmacological Effects of 2C-B in Humans: An Observational Study

Frontiers in Pharmacology March 13, 2018 Esther Papaseit, Marta Torrens, Mireia Ventura et al. 61 citations

2C-B, a psychedelic similar to mescaline, acts on serotonin receptors and produces mild psychedelic and stimulant-like effects. In an observational study, 16 healthy experienced users took 10–20 mg orally. The drug increased blood pressure and heart rate, elevated scores on scales for euphoria, liking, and stimulation, and altered perceptions of distances, colors, shapes, and lights. Five participants reported mild hallucinations. Peak 2C-B levels in saliva occurred at 1 hour, and peak cortisol at 3 hours. The effects resemble those of other serotonin-acting drugs.

MDMA interactions with pharmaceuticals and drugs of abuse

Expert Opinion on Drug Metabolism & Toxicology March 31, 2020 Esther Papaseit, Clara Pérez‐mañá, Marta Torrens et al. 34 citations

MDMA (ecstasy) is a widely used recreational stimulant. Users often combine it with other drugs to enhance effects, reduce toxicity, or manage comedowns, which increases the risk of severe toxicity. This review covers known interactions between MDMA and other pharmaceuticals or drugs of abuse, offering clinical recommendations. The authors note that few published studies exist and documented clinically significant interactions are scarce. Experimental evidence shows that interactions are especially relevant when MDMA is taken with drugs metabolized by the CYP2D6 enzyme, due to MDMA's inhibitory effect, and during repeated MDMA use.

Mephedrone and Alcohol Interactions in Humans

Frontiers in Pharmacology January 28, 2020 Esther Papaseit, Clara Pérez-mañá, Elizabeth B. de Sousa Fernandes Perna et al. 27 citations

Combining mephedrone with alcohol amplifies cardiovascular effects and intensifies euphoria and well-being compared to either drug alone, while mephedrone reduces the sedative effects of alcohol. In a double-blind, placebo-controlled trial with 11 male volunteers, the combination increased blood pressure, heart rate, and subjective feelings of euphoria. Mephedrone alone and alcohol alone were also tested. The results suggest that the abuse liability of mephedrone is greater when taken with alcohol, similar to other psychostimulants like amphetamines and MDMA.

Pharmacological effects of methylone and MDMA in humans

Frontiers in Pharmacology February 17, 2023 Lourdes Poyatos, Clara Pérez‐mañá, Olga Hladun et al. 26 citations

Methylone, a common synthetic cathinone used as a substitute for MDMA, produces similar acute effects in humans. In a controlled trial with 17 experienced psychostimulant users, a single 200 mg oral dose of methylone increased blood pressure and heart rate and induced pleasurable effects including stimulation, euphoria, wellbeing, enhanced empathy, and altered perception. Methylone's effect profile resembled MDMA's but with a faster onset and earlier disappearance of subjective effects. The findings suggest methylone's abuse potential is comparable to that of MDMA in humans.

Methylone and MDMA Pharmacokinetics Following Controlled Administration in Humans

International Journal of Molecular Sciences November 23, 2022 Lourdes Poyatos, Alfredo Fabrizio Lo Faro, Diletta Berardinelli et al. 22 citations

After controlled oral doses of 50–200 mg methylone given to 12 male volunteers, plasma concentrations increased in proportion to dose. Maximum concentrations ranged from 153 ng/mL at the lowest dose to 604 ng/mL at the highest dose. The drug was absorbed rapidly, reaching peak levels in 1.5–2 hours, and had a half-life of about 6 hours. Its metabolite HMMC reached peak concentrations 10–14 times lower than methylone. Unlike MDMA, methylone showed linear pharmacokinetics across the dose range. A validated LC-MS/MS method was used to measure methylone, MDMA, and their metabolites in plasma.

Acute Effects of 2C-E in Humans: An Observational Study

Frontiers in Pharmacology March 18, 2020 Esther Papaseit, Marta Torrens, Mireia Ventura et al. 20 citations

2C-E, a psychedelic phenylethylamine similar to mescaline, acts as a partial agonist at serotonin 2A, 2B, and 2C receptors and inhibits norepinephrine and serotonin uptake. In an observational study, ten recreational psychedelic users self-administered single oral doses of 2C-E (6.5–25 mg). The drug induced alterations in perception, hallucinations, and euphoric mood, with saliva concentrations peaking 2 hours after administration. The effects resembled those of 2C-B and other serotonin-acting drugs.

Key interindividual determinants in MDMA pharmacodynamics

Expert Opinion on Drug Metabolism & Toxicology January 5, 2018 Esther Papaseit, Marta Torrens, Clara Pérez‐mañá et al. 20 citations

MDMA (ecstasy) produces amphetamine-like euphoria and well-being, increases empathy, and induces pro-social effects that drive recreational use and suggest therapeutic potential. This review examines interindividual differences in MDMA's pharmacodynamics, focusing on sex-gender, race-ethnicity, genetic differences, interactions, acute toxicity, and therapeutic use. Acute MDMA effects are more pronounced in women than men. Very limited data exist on race-ethnicity effects. MDMA metabolism involves polymorphic enzymes that slightly alter plasma concentrations and effects. The small number of subjects in acute-effect trials limits evaluation of interindividual factors and prevents clear conclusions about their influence, which should be considered in therapeutic studies.

Development of enantioselective high-performance liquid chromatography-tandem mass spectrometry method for the quantitative determination of 3,4-methylenedioxy-methamphetamine (MDMA) and its phase-1 metabolites in human biological fluids.

Journal of pharmaceutical and biomedical analysis January 20, 2024 Alfredo Fabrizio Lo Faro, Giorgia Sprega, Diletta Beradinelli et al. 14 citations

Enantioselective high-performance liquid chromatography-tandem mass spectrometry methods were developed to quantify MDMA and its phase-1 metabolites HMA, HMMA, and MDA in human plasma, sweat, oral fluid, and urine. Two polysaccharide-based chiral columns achieved baseline separation of most enantiomer pairs: the Lux AMP column separated MDMA, HMA, and HMMA enantiomers but not MDA; the Lux i-Amylose-3 column separated MDMA, HMMA, and MDA enantiomers but not HMA. Analysis took under 4 minutes with one column and under 6 minutes with the other. Both methods were validated and applied to biological fluids, confirming enantioselective metabolism of MDMA.

Acute pharmacological effects of α-PVP in humans: a naturalistic observational study.

Frontiers in pharmacology January 1, 2025 Georgina De la Rosa, Esther Papaseit, Olga Hladun et al. 7 citations

Alpha-pyrrolidinopentiophenone (α-PVP), a synthetic cathinone similar to MDPV and cocaine, produces rapid-onset psychostimulant and empathogenic effects after a single intranasal dose. In nine participants with prior psychostimulant use, 10 mg or 20 mg of α-PVP caused an acute increase in blood pressure and heart rate that peaked 40 minutes after administration. Subjective effects appeared quickly and resolved within 3 to 5 hours. The drug's psychostimulant properties resembled those of cocaine, and its empathogenic effects were similar to those of MDMA and other cathinones like methylone.

Drug and MDMA Interactions Implications for Public Health

Handbook of Substance Misuse and Addictions January 1, 2022 Esther Papaseit, Magí Farré, Clara Pérez-mañá

Public health efforts must balance preventing illicit drug use with ensuring access to medicines that have abuse potential. Drug interactions for drugs of abuse, unlike those for medicines, are largely underexplored and not part of clinical routine. MDMA (ecstasy, molly) exemplifies this: it is a popular recreational psychostimulant and is being evaluated for treating post-traumatic stress disorder. Understanding inter- and intraindividual factors, modulation factors, and potential interactions is crucial to assess intoxication risk for both recreational users and patients in future MDMA-assisted therapy.