Gregor Hasler

M.D., LSD researcher, psychiatrist, psychotherapist and professor at University of Fribourg


Adverse effects of psychedelics: are they all part of the therapeutic process?

Talk date & time:
Saturday 12:00-13:30


In medicine, an adverse effect is an undesired harmful effect resulting from a medication or other intervention. In psychedelics research and therapy, the term “adverse effects” is rarely used because there is the assumption that all negative, unpleasant effects are part of the therapeutic process. Is this really true? The minority of psychedelic studies that systematically assess this show that unpleasant effects are very common and that anxiety, nausea and headaches are the most prevalent ones. Are these symptoms part of the therapeutic process? Are they side effects related to the main therapeutic effect? Or are they adverse effects in the strict sense of the term which we should systematically assess and document? In my talk, I want to initiate a discussion about these important questions.


Gregor Hasler, M.D. was born in Basel, Switzerland. He is a Swiss psychiatrist and psychotherapist. From 2003 to 2006 he was a Visiting Research Fellow at the Mood and Anxiety Disorders Program at the National Institute of Mental Health (supervisors: Wayne C. Drevets, Dennis S. Charney, Husseini Manji). Using PET imaging, magnetic resonance spectroscopy, pharmacological challenges in mood, anxiety and eating disorders (GABA, glutamate systems, catecholamines, serotonin). Dr. Hasler is Professor and Chair of Psychiatry at the University of Fribourg, Switzerland. His research is supported by the Swiss National Science Foundation, and he has received numerous awards for his scientific work, including the NARSAD Independent Investigator Award and the Robert Bing Award from the Swiss Academy of Medical Sciences. He is the president of the Swiss Society for Pharmacovigilance in Psychiatry and president of the Swiss Society for Bipolar Disorder.