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Dear study participant,

Thank you for your interest in participating in our online survey! 

What is the study about?

The use of psychoactive substances such as LSD, psilocybin, cocaine or amphetamine has various effects on consciousness. A distinction can be made between the immediate effects of the substances and the effects that occur in the days after ingestion. This online survey examines the psychoactive effects that occur in the days following ingestion. We want to find out how after-effects differ between substances.  

How long does it take to participate and what is in it for me?

Participating in the survey will take about 25 minutes. Participation is voluntary. You can cancel the questionnaire at any time by closing your browser window. There is no direct benefit to you by participating. However, by sharing your valuable experience, you make an important contribution to the research of the effects of psychoactive substances and their clinical benefits.

Is participation anonymous?

Participation in the survey is completely anonymous and no IP address will be saved. We will ask for some personal data such as age and gender at the end of the questionnaire. It is not possible to trace back who completed the questionnaire with this information. The study is approved by the Ethics Commission of the Charité - Universitätsmedizin Berlin.

Who can participate in the study?

Any person can participate in this study who

  • is at least 18 years old 
  • has ingested any of the following substances in the last four weeks:
    • psychedelics / serotonergic hallucinogens (e.g. LSD, psilocybin, ayahuasca or mescaline)
    • amphetamines (speed) or methaphetamines (crystal meth) or cocaine
    • opioids (e.g. heroin, fentanyl)
  • has very good knowledge of German or English

Who can I contact if I have any questions?

If you have any questions about the study, please contact the research director Dr. Tomislav Majić (e-mail: tomislav.majic@charite.de). If you would like to send us comments on the study, you have the opportunity to do so in a text field at the end of the questionnaire.

Thank you for your cooperation

Dr. Tomislav Majić      Dr. Ricarda Evens      Dr. Timo T. Schmidt

AG Psychotrope Substanzen, Psychiatrische Universitätsklinik der Charité im St. Hedwig-Krankenhaus