Effects of Psilocybin in Anorexia Nervosa

This open-label pilot study seeks to investigate the safety and efficacy of psilocybin in persons with chronic anorexia nervosa (AN). Psilocybin has previously been demonstrated to decrease depression and anxiety and increase long-term positive behavior change in other populations. The investigators seek to determine whether similar changes can be safely produced in people with AN when psilocybin is administered in a supportive setting with close follow-up. The investigators' primary hypotheses are that psilocybin is safe to administer in people with AN, that it will reduce measures of anxiety and depression, and that it will lead to increased quality of life. The investigators will also assess a number of exploratory measures related to eating disorder pathophysiology.