In this interdisciplinary paper we will characterise the phenomenology of ayahuasca visions from two main viewpoints. On the one hand, we scrutinise the complicated matters of psychedelics in context of consciousness studies. On the other, we will mobilise some of the basic conceptions of the phenomenological tradition - relying on Merleau-Ponty's and Husserl's phenomenology-, to differentiate between the features of perception, hallucination, and vision. We propose that actual research concerning the problems of psychointegration can be extended by utilizing the heuristic value of basic phenomenological concepts (i.e. intentionality, body schema, fantasy). As an overall goal, we intend to show that Merleau-Ponty's late ontology can be a useful explanatory tool for circumscribing the irrational and chaotic experiences induced by psychoactive substances (in arguing for this point we rely substantially on Beny Shannon's phenomenological ideas).