Uses methamphetamine regularly and identifies it as their primary drug
Has a goal of quitting methamphetamine use
Able and willing to abstain from methamphetamine and other non-prescribed drugs for at least 24 hours prior to and throughout psilocybin dosing sessions
Currently living indoors with stable housing anticipated for the duration of the study
Has a text-capable cellphone
Willing to use highly effective contraception and not donate sperm throughout the study
Able to participate in study procedures in English
You may not be if
History of any primary psychotic disorder (e.g., schizophrenia or schizoaffective disorder), bipolar I disorder, or certain other psychiatric conditions as determined by study assessment
Current moderate-to-severe opioid, alcohol, or sedative use disorder (Note: people on stable doses of buprenorphine or methadone may be eligible)
Currently taking certain medications that may interact with psilocybin
Recent use of a psychedelic drug
Certain significant heart, liver, or kidney conditions
Uncontrolled high blood presure (i.e., \>150/90 mmHg)
History of stroke or seizure in the past year
Current pregnancy or breastfeeding
Current involvement in the criminal legal system that would be expected to interfere with study participation
Current or planned enrollment in a contingency management program or another investigational substance use treatment trial within the past month
Note: Additional eligibility criteria apply. Certain criteria and thresholds are not listed here to preserve the scientific integrity of the study.
