Aims: To better understand the long-term effects of naturalistic psychedelic use and the factors that influence them.

Method: A mixed methods study consisting of an online survey (N = 603) and follow-up semi- structured interviews (N = 26) was conducted to broadly explore participants’ psychedelic use and its long-term effects.

Results: Two major themes related to long-lasting effects of naturalistic psychedelic use were identified. The first major theme identified psychedelic use as an activity that transforms participants’ perspective of themselves, others, and the world, leading to the second major theme wherein participants experienced an overall improvement in the quality of their lives.

Conclusion: For the majority of psychedelic users, naturalistic psychedelic use produced personally meaningful changes in users’ perspectives of themselves, others, and the world. These changes include greater self-understanding, deepened and expanded spiritual beliefs, more altruistic attitudes, a more positive outlook on life, greater self-acceptance and acceptance of others, a deepened connection with oneself, others, and the world, as well as an overall improvement in participants’ interpersonal relationships, mental health, and quality of life. Although, a small minority of users also reported lasting negative effects.