An entheogen (""generating the divine within"") is a chemical substance used in a religious, shamanic, or spiritual context that may be synthesized or obtained from natural species. The chemical induces altered states of consciousness, psychological or physiological (e.g., bullet ant venom used by the Satere-Mawe people). Entheogens can supplement many diverse practices for transcendence, and revelation, including meditation, yoga, and prayer, psychedelic and visionary art, chanting, and music including peyote song and psytrance, traditional medicine and psychedelic therapy, witchcraft, magic, and psychonautics.Entheogens have been used in a ritualized context for thousands of years; their religious significance is well established in anthropological and modern evidences. Examples of traditional entheogens include psychedelics like peyote, psilocybin mushrooms, and ayahuasca, psychedelic-dissociatives like Tabernanthe iboga, atypical psychedelics like Salvia divinorum, quasi-psychedelics like cannabis and Ipomoea tricolor, deliriants like Amanita muscaria. Traditionally a tea, admixture, or potion like ayahuasca or bhang have been compounded through the work of a shaman or apothecary.With the advent of organic chemistry, there now exist many synthetic drugs with similar psychoactive properties, many derived from these plants. Many pure active compounds with psychoactive properties have been isolated from these respective organisms and chemically synthesized, including mescaline, psilocybin, DMT, salvinorin A, ibogaine, ergine, and muscimol. Semi-synthetic (e.g., LSD used by the Neo-American Church) and synthetic drugs (e.g., DPT used by the Temple of the True Inner Light and 2C-B used by the Sangoma) have also been developed. Cannabis is the world's most widely used psychedelic drug and part of the cannabis culture, while medical cannabis have contributed to the development of modern drug paraphernalia like the vaporizer used by hospitals. However, Cannabis is always considered a quasi-psychedelic drug, even with cannabis strains that have been bred to intensify the psychedelic characteristics.More broadly, the term entheogen is used to refer to any psychoactive drugs when used for their religious or spiritual effects, whether or not in a formal religious or traditional structure. This terminology is often chosen to contrast with recreational use of the same drugs. Studies such as Timothy Leary's Marsh Chapel Experiment and Roland Griffiths' psilocybin studies at Johns Hopkins have documented reports of mystical/spiritual/religious experiences from participants who were administered psychoactive drugs in controlled trials. Ongoing research is limited due to widespread drug prohibition; however, some countries have legislation that allows for traditional entheogen use.