Can You Predict a ‘Bad’ Psychedelic Trip?

Evan Lewis-Healey
5 min readApr 14, 2021

New research from Central Michigan University highlights the states and traits that predict negative experiences in a psychedelic session.

Photo by Diana Satellite on Unsplash

Neuroscientist, author, and well-travelled psychonaut Sam Harris, describes a memorably “bad” acid trip of his twenties during a 2011 podcast episode. After watching the sunrise in solitude, in a rowboat overlooking the Annapurna range of Nepal, Harris ingested 400 micrograms of LSD. What ensued was, to the author’s recall, one of the most harrowing experiences he could conceive of. Harris recalls his distressing experience:

“For the next several hours my mind became a perfect instrument of self-torture. All that remained was a continuous shattering and terror for which I have no words. An encounter like that takes something out of you. Even if LSD and similar drugs are biologically safe, they have the potential to produce extremely unpleasant and destabilizing experiences.”

Harris’s testimonial highlights an important point: as the psychedelic renaissance is upon us, it’s increasingly relevant to acknowledge the negative, as well as the positive states that LSD, magic mushrooms, and other psychedelics can induce. There’s still a great deal that we simply don’t know about how psychedelics can affect us. Why do some people have one of the most significant experiences of their life under psychedelics, while others are terrified by the ordeal?

As clinicians attempt to integrate psychedelic therapy into Western medicine, being able to predict how a person reacts to a psychedelic trip is a principal aim that can minimise long-term harm.

What is a Bad Trip?

“Bad trips” are memorable and unpleasant experiences while under the influence of psychedelics. Although the quality of these bad trips can vary from person to person, they are often characterised by frightening hallucinations, and feelings of panic, fear, and anxiety.

Modern psychedelic research has undergone stringent safety protocols; this careful procedure of intensive…



Evan Lewis-Healey

PhD candidate at Cambridge University. Studying the cognitive neuroscience of altered states of consciousness.