The purpose of this review article is to give a summary of the literature on the use of psychedelic drugs, such as psilocybin, LSD, ayahuasca, and MDMA, in the treatment of various mental health conditions, such as depression, anxiety, PTSD, and substance use disorders. This review's main goal is to highlight recent human studies on the use of particular psychedelic drugs, like psilocybin, LSD,...