Effect of Ketanserin After LSD Administration on the Acute Response to LSD in Healthy Subjects
试验速览
- 阶段
- 1 期
- 状态
- 已完成
- 发起方
- 入组人数
- 24
- 试验地点
- 1
- 主要终点
- Duration of subjective response
研究概览
简要总结
LSD (lysergic acid diethylamide) is a serotonergic (5-HT) hallucinogen widely used for recreational and/or ethnomedical purposes. LSD is thought to induce its prototypical psychedelic effects primarily via stimulation of the 5-HT2A receptor. This study investigates whether an LSD experience can be attenuated and shortened using 5-HT2A receptor antagonist ketanserin administration after LSD once the psychedelic effects have established.
详细描述
LSD is a so-called "classic" or serotonergic hallucinogen or psychedelic.The effects of LSD have been frequently investigated in the past in both healthy participants and patients. In these studies, LSD produced acute transient alterations in waking consciousness including visual perceptual alterations, audio-visual synesthesia, derealization and depersonalization. Moreover, several of these studies described robust and sustained effects of LSD in patients suffering from addiction, anxiety and depression.
Its psychedelic effects are mainly attributed to its potent partial 5-HT2A receptor agonism. Consistently, administration the 5-HT2A receptor antagonist ketanserin (40 mg) prior to the administration of LSD (100 μg) almost completely prevented the acute effects of LSD in another study of our research group (NCT03321136). The present study hypothesis is that ketanserin (40 mg) administered 1h after LSD shortens and reduces the acute subjective effects of LSD (100 μg) compared to LSD alone (100 μg) followed by placebo in healthy humans. Such a finding would confirm a primarily competitive antagonism of ketanserin and LSD at the 5-HT2A receptor in vivo and indicate that LSD produces its psychedelic effects only when present at the receptor.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Triple (Participant, Care Provider, Investigator)
入排标准
- 年龄范围
- 25 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Age between 25 and 65 years old
- •Sufficient understanding of the German language
- •Understanding of procedures and risks associated with the study
- •Willing to adhere to the protocol and signing of the consent form
- •Willing to refrain from the consumption of illicit psychoactive substances during the study
- •Abstaining from xanthine-based liquids and foods from the evenings prior to the study sessions to the end of the study days
- •Willing not to operate heavy machinery within 48 hours after substance administration
- •Willing to use double-barrier birth control throughout study participation
- •Body mass index between 18-29 kg/m2
排除标准
- •Chronic or acute medical condition
- •Current or previous major psychiatric disorder
- •Psychotic disorder or bipolar disorder in first-degree relatives
- •Hypertension (>140/90 mmHg) or hypotension (SBP<85 mmHg)
- •Hallucinogenic substance use (not including cannabis) more than 20 times or any time within the previous two months
- •Pregnancy or current breastfeeding
- •Participation in another clinical trial (currently or within the last 30 days)
- •Use of medication that may interfere with the effects of the study medication
- •Tobacco smoking (>10 cigarettes/day)
- •Consumption of alcoholic beverages (>20 drinks/week)
研究组 & 干预措施
100 μg LSD + Ketanserin placebo
干预措施: Lysergic Acid Diethylamide (Drug)
100 μg LSD + Ketanserin placebo
干预措施: Ketanserin Placebo (Drug)
100 μg LSD + Ketanserin (40mg)
干预措施: Lysergic Acid Diethylamide (Drug)
100 μg LSD + Ketanserin (40mg)
干预措施: Ketanserin (Drug)
结局指标
主要结局
Duration of subjective response
时间窗: 12 months
Visual Analog Scales (VAS) will be repeatedly used to assess subjective alterations in consciousness over time. VAS will be presented as 100 mm long horizontal lines marked with "not at all" on the left and "extremely" on the right. The following VAS will be used: "any effect", "good effect", "bad effect", "fear", "stimulated", "nausea", "tiredness", "alteration of hearing", "alteration of vision", "synesthesia", "alteration in sense of time", "the boundaries between myself and my surroundings seemed to blur", "talkative", "open", "trust" and "my focus is directed: outward/inward". Subjects will mark the scale with vertical lines.
Extent of subjective response
时间窗: 12 months
Visual Analog Scales (VAS) will be repeatedly used to assess subjective alterations in consciousness over time. VAS will be presented as 100 mm long horizontal lines marked with "not at all" on the left and "extremely" on the right. The following VAS will be used: "any effect", "good effect", "bad effect", "fear", "stimulated", "nausea", "tiredness", "alteration of hearing", "alteration of vision", "synesthesia", "alteration in sense of time", "the boundaries between myself and my surroundings seemed to blur", "talkative", "open", "trust" and "my focus is directed: outward/inward". Subjects will mark the scale with vertical lines.
Plasma concentrations of LSD
时间窗: 12 months
LSD plasma concentrations will be measured repeatedly over time using LC-MS/MS techniques (nanogram per milliliter scale).
Plasma concentrations of Ketanserin
时间窗: 12 months
LSD plasma concentrations will be measured repeatedly over time using Liquid chromatography-mass spectrometry (LC-MS)/MS techniques (nanogram per milliliter scale).
次要结局
- 5 dimensions of altered state of consciousness (5D-ASC) profile total score(12 months)
- Adjective mood rating scale (AMRS)(12 months)
- States of consciousness questionnaire (SCQ)(12 months)
- Blood pressure(12 months)
- Heart rate(12 months)
- Body temperature(12 months)
- Pupil diameter(12 months)
- Elliot Humility Scale (EHS)(12 months)
- Jankowski Humility Scale (JHS)(12 months)
- Arnett Inventory of Sensation Seeking (AISS-d)(12 months)
- Freiburger Persönlichkeitsinventar (FPI)(12 months)
- Saarbrücker Persönlichkeitsfragebogen (SPF)(12 months)
- Defense Style Questionnaire (DSQ-40)(12 months)