Regular use of peyote, a hallucinogen-containing cactus, in a religious setting among Navajo Native Americans does not appear to cause long-term psychological or cognitive deficits. In a study comparing three groups—61 Native American Church members who regularly ingested peyote, 36 individuals with past alcohol dependence who had been sober for at least two months, and 79 individuals with minimal substance use—the peyote group showed no significant differences on a mental health inventory or ten neuropsychological tests compared to the minimal-use group. In contrast, the former alcoholic group showed significant deficits on all mental health scales and two neuropsychological measures. Total lifetime peyote use was not linked to worse performance. These findings may not apply to illicit hallucinogen users.
A repeat survey of American psychiatrists in 2022-23 found a striking increase in optimism about the therapeutic use of hallucinogens compared to 2016. Among 131 respondents (13.1% response rate), 80.9% moderately or strongly believed hallucinogens show promise for psychiatric conditions, and 60.8% for substance use disorders. Large majorities supported research into therapeutic potential (93.9% for psychiatric conditions, 88.6% for substance use disorders) and federal funding of clinical trials. Concern about risks decreased, and 50.4% reported moderate or strong intentions to incorporate hallucinogen-assisted therapy into their practice if regulatory approval is granted.