Psychedelic therapy are therapeutic practices involving psychedelic drugs, such as LSD, psilocybin, DMT, and MDMA. In psychedelic therapy, in contrast to conventional psychiatric medication taken by the patient regularly or as-needed, patients generally remain in an extended psychotherapy session during the acute psychedelic activity with additional sessions both before and after in order to help integrate experiences with the psychedelics. Psychedelic therapy has been compared with the shamanic healing rituals of indigenous people. Researchers identified two main differences: the first is the shamanic belief that multiple realities exist and can be explored through altered states of consciousness, and second the belief that spirits encountered in dreams and visions are real.