En la cultura mazateca (Oaxaca, México), los trances de posesión se manifiestan a través de estados de conciencia alterados. Los chamanes mazatecos realizan curaciones ingiriendo el teonánacatl, crane de Dios, un hongo alucinógeno. Es desde este estado de conciencia estático aprovechan el proceso de expurgación, enfocado a la expulsión de males.In the Mazatec culture (Oaxaca, Mexico), posession trances express themselves through states of altered consciousness. The sinahé (mazateccan shamans) perform curing séances by ingesting teonanacatl ("Flesh of God"), a psylocibine-bearing mushroom. It is from this ecstatic state of consciousness that they approach their expurgation processes, aiming at the expulsion of evil entities, which can cause the loss of the spirit or even death. We establish comparative aspects with the use of posession in the Occidental Chrisüan tradition and the role of exorcists.