The authors present the results of investigation carried out in the ayahuasca analogues research field (pharmahuasca) using a species of Phalaris (Gramineae) native to or naturalized in Italy as source of tryptamine alkaloids. As a source of B-carboline alkaloids, the seeds of Peganum harmala (Zygophyllaceae), a plant living in Mediterranean countries including Italy, have been used. As a result of some auto-experiments aimed at reproducing a kind of 'ayahuasca effect' the mixing of the acqueous extract: of young leaves of Phalaris aquatica L. and seeds of P.harmala proved to be strongly psychoactive; this further confirms the validity of the model of the action of alkaloids contained in the ayahuasca potions, which is the basis of the principles of pharmahuasca. With regard to the quantities of psychoactive indolic alkaloids in P.aquatica and P.arundinacea, great deal of literature exists from the agronomic and veterinary fields. Genetic, environmental, physiological and cultural factors which may significantly influence ihe concentration of these alkaloids are discussed. Lastly, the results of a series of chemical analysis carried out on the main European species of the Phalaris genus will be referred to, up to now unexplored from the point of view of its psychoactive indolic alkaloid content