The (ca. 100 CE) Chinese pharmacopeia Shennong Ben Cao Jing (Shennong’s Classic of Materia Medica) described the use of mafen 麻蕡 “cannabis fruit/seeds”:

To take much makes people see demons and throw themselves about like maniacs (多食令人見鬼狂走). But if one takes it over a long period of time one can communicate with the spirits, and one’s body becomes light (久服通神明輕身).