Well, since the drugs influences are obvious with Kyuss, it could have something to do with a entheogenic plant ayahuasca, known by native Amazonians as "La Purga" - "The Purge" (due to its inducement of nausea and vomiting). Traditional ceremonies are held in which those who eat the plant purge themselves of evil spirits, before being "reborn". Of course, there are many psychotropic plants and substances that are taken in rituals like this (such as peyote), but it's just a thought.
Well, since the drugs influences are obvious with Kyuss, it could have something to do with a entheogenic plant ayahuasca, known by native Amazonians as "La Purga" - "The Purge" (due to its inducement of nausea and vomiting). Traditional ceremonies are held in which those who eat the plant purge themselves of evil spirits, before being "reborn". Of course, there are many psychotropic plants and substances that are taken in rituals like this (such as peyote), but it's just a thought.