Illicit use of LSD or psilocybin, but not MDMA or nonpsychedelic drugs, is associated with mystical experiences in a dose-dependent manner.

Psychedelic drugs have long been known to be capable of inducing mystical or transcendental experiences. However, given the common "recreational" nature of much present-day psychedelic use, with typical doses tending to be lower than those commonly taken in the 1960s, the extent to which illicit use of psychedelics today is associated with mystical experiences is not known. Furthermore the mild psychedelic MDMA ("Ecstasy") is more popular today than "full" psychedelics such as LSD or psilocybin, and the contribution of illicit MDMA use to mystical experiences is not known. The present study recruited 337 adults from the website and newsletter of the Multidisciplinary Association for Psychedelic Studies (MAPS), most of whom reported use of a variety of drugs both licit and illicit including psychedelics. Although only a quarter of the sample reported "spiritual" motives for using psychedelics, use of LSD and psilocybin was significantly positively related to scores on two well-known indices of mystical experiences in a dose-related manner, whereas use of MDMA, cannabis, cocaine, opiates and alcohol was not. Results suggest that even in today's context of "recreational" drug use, psychedelics such as LSD and psilocybin, when taken at higher doses, continue to induce mystical experiences in many users.