It is a known fact that ayahuasca and yagé drinks consist of a pair of plants: vine or leaves of ayahuasca (Banisteriopsis caapi) and leaves of chacruna (Psychotria viridis) or oko yagé (Diplopterys cabrerana). The last two contain the visionary DMT molecule, while the vine produces the harmine and harmaline alkaloids. The molecules of the vine, due to their property of inhibiting the MAO enzymes, allow DMT to be absorbed in the gut and to manifest its visionary effects. This is the basic plant formula, which we can define the mother brew of ayahuasca and yagé. To this mother brew the natives of the Amazon have added many other plant ingredients. This articles looks at the wide variety of plants that shamans add to their ayahuasca brews and considers potential elements of their effects.
The main reason for infusing additional ayahuasca plant allies is to enhance, modify, or modulate the visionary effect of the traditional brew.
Bringing together the data presented by the three main studies that have dealt with what plants shamans have added to ayahuasca (Pinkley, 1969; McKenna et al., 1986; Bianchi and Samorini, 1993), we have identified more than 80 plant species, but I suspect their number is greater, including perhaps between 100 and 200 species. Some of these plants are used extensively among the different Amazonian ethnic groups, while others are used as additives of ayahuasca or yagé by individual ethnic groups or even by individual vegetalistas, as a result of some local experiment and knowledge.
One could raise a complaint about the lack of scientific studies on these plants, observing how the little research developed so far has always confirmed and “justified” the enhancing or modulating use of these additives.

These plant additions are mostly carried out at the time the mother brew is cooked, adding the chosen plant directly to the pot. The main reason for these additions is to enhance, modify, or modulate the visionary effect of the traditional drink, choices and preferences that highlight a very original range of nuances and perceptive refinement of visionary effects. In the Peruvian Amazon the Sharanahuas add to ayahuasca the leaves of a species of Psychotria to “give the impression of coldness and to produce less visions,” thus seeking a precise modulation that reduces the “grandeur” of the visions and at the same time their emotional impact. Peruvian vegetalistas add a species of Euphorbia to ayahuasca that they give to the apprentice, with the aim of improving his voice while learning icaros singing. In other contexts, certain plants are added to the boiling pot of ayahuasca in difficult diagnostic cases, as an aid to identify the cause of the patient’s illness that the vegetalista is treating. This happens among the Makunas of the Colombian river Popeyaca, which in these difficult situations add to the mother brew some pounded leaves of Malouetia tamaquarina to “better see” the origins of the disease.
The ayahuasca/yagé cooking pot could be interpreted as a neuroalchemic crucible, intended as a material tool of what I have called “psychotropic complexes” in my studies; that is, those contexts of traditional use of intoxicant sources that start from a psychoactive mother brew assumed as a visionary default; a visionary base that is modulated with a wide range of additives, to enhance the effects of the mother-brew, or to vary the color spectrum of the visions (more purple, more red, etc.), or to change the emotional levels or the extrasensory perceptions, or to induce specific visionary and thought contents.
We can therefore speak of an ancient Dionysian psychotropic complex, where the mother-brew was the grape wine of classical Greece; or of pulque, the fermented sap of agave used in Mexico since pre-Aztec times; or of chicha, the Latin American beer made mainly with corn. It is safe to say that in chicha everything has been added, the most weird ingredients, even live frogs and toads. Similarly, we can speak of a “psychotropic complex of ayahuasca” and, unlike the previous examples, the ayahuasca/yagé mother-brews are not based on alcohol sources. In all these complexes, ancient and modern, the number of additive ingredients available is always high—from a few tens to several hundred—and is subject to continuous expansion. This is the case of the same ayahuasca, whose list of additive plants is expanding along with the activity of research and acquisition of new knowledge by the Amazonian vegetalistas.
We meet one of the most advanced contexts of this “research around a pot and its contents” among the Shipibo-Conibos and other ethnic groups of the Peruvian river Ucayalli.
We must not forget a very important quality of the Amazonian shamans, that is to say that they are also researchers, with that meaning of “research” similar if not identical to the one I adopt in my case of Western ethnobotanists, and which originates from the concept of “looking for something.” The same ayahuasca and yagé brews are to be seen as the ultimate elaboration—in a chronological and qualitative sense—of a series of combinations tested with a spirit of experimentation. The Amazonian vegetalistas have always been great experimenters, trying everything on their skin, and the discovery of ayahuasca and yagé spilled from their neuroalchemic crucibles can be seen, not only as a gift of nature or of benevolent deities, but also as a reward for their centuries-old and constant research around a pot and its contents.
We meet one of the most advanced contexts of this “research around a pot and its contents” among the Shipibo-Conibos and other ethnic groups of the Peruvian river Ucayalli, where the important concept of “master plant” assumes its fullest role: it is the same ayahuasca brew that teaches to the vegetalista the qualities of other plants. To evaluate the properties of an unknown plant—if toxic, medicinal, intoxicant, etc.—the vegetalista places a small portion, a leaf, some seeds, a small piece of root, inside the ayahuasca brew that is cooking in the pot. It will be the same ayahuasca, once ingested and through its visionary effects, to communicate the qualities of that plant element directly to the vegetalista. With a Western perspective and terminology, these forest shamans make a diagnostic use of ayahuasca not only on patients but also on the surrounding flora. The ayahuasqueros of this region of the Peruvian Amazon state that most of their knowledge of medicinal plants has been acquired through this technique.
In Western literature an anecdote, which has real roots, is reported quite frequently concerning an anthropological researcher who pointed out to a vegetalista the hallucinogenic mushroom Psilocybe cubensis that grew on the cow dung of the region. The vegetalista collected one mushroom and later added it to the pot of ayahuasca in preparation, and he was surprised for the interesting indications that he reported having received from ayahuasca on that mushroom.
With the psychotropic complexes we find ourselves facing refinement and not just complexity—one could say refinement in complexity—of the modus operandi of the expert of visionary sources; combinatorial knowledge that even Western culture had reached in its past. Just think of Dionysian pots, Celtic cauldrons, or those of the “witches” of the European Middle Ages and the Renaissance.

Looking at the list of plants added to the ayahuasca/yagé from the point of view of a Western scholar, a first look is directed at the species of the same genera as those employed in the mother brews. In addition to B. caapi, we know that another vine, Banisteriopsis muricata, is used at least by the Waoranis of Ecuador to replace B. caapi, and that it produces the same active principles in quantities not inferior to the latter. It is strange how this liana, the most widespread in the genus Banisteriopsis, present from Mexico to Argentina, appears not to be known in other regions for its intoxicating properties, especially triggering or reinforcing the effects of other intoxicant sources. We still know of another species, B. martiniana, used in the Colombian Amazonia as a source of an intoxicating drink. In the genus Psychotria, in addition to the classic chacruna (P. viridis), the Sharanahuas and Kulinas of the southwestern Amazon add to the brew Psychotria carthaginensis. Biochemical analyses have shown discrete concentrations of DMT in its leaves, confirming the validity of its ethnic use. We also know of the curious “nature’s joke”, which caused DMT to be produced by a liana, the oko yagé, previously identified as a species of Banisteriopsis and now classified as Diplopterys cabrerana. From a liana used as an inebriating source in the context of the “ayahuasca complex,” both the natives and Western scholars would have expected the same MAO-inhibiting substances present in the caapi vine; instead “only” high concentrations of DMT were found, justifying the addition of its leaves to the yagé in the area of the Colombian Putumayo as well as of the Amazonian Ecuador. Kofans add the leaves of oko yagé to their brew “to increase visions and make them last longer.”
A series of plants added to the ayahuasca/yagé would therefore do nothing but reinforce the effect without substantially modifying the qualitative aspects, as they produce the same tryptamine alkaloids (DMT) or MAO-inhibitors (harmine, harmaline) present in the ayahuasca and yagé brews. This group can be considered as that of the reinforcing additives.
One of these plants attracts attention, Tetrapterys mucronata, which is added to the yagé by some Colombian ethnic groups and whose bark can produce both types of alkaloids; in practice, we would be in the presence of an “ideal” plant, which could collect the principle of “two plants in one,” simultaneously satisfying the need for the presence of MAO-inhibitors and of hallucinogenic tryptamines. This would find confirmation in the use of this plant as the only ingredient to prepare an intoxicating drink that Richard Schultes, one of the fathers of modern ethnobotany, reported having observed and even tried on himself when in the 1940s he was among the Maku of the Brazilian Rio Tikié. The recent chemical analyses on this plant offer a confirmation that highlights the profound traditional knowledge, and that native shamans know their stuff well in matters of combinatorial art.
Other plants, although they do not specifically produce harmine and harmaline, produce compounds that are equally endowed with MAO-inhibitory properties and therefore reinforce the effect of the drink. This is the case of Brunfelsia species, whose bark, leaves, and roots are added to the mother brew by Colombian and Ecuadorian ethnic groups. Although they are Solanaceous plants, they do not produce the hallucinogenic tropane alkaloids, but they produce scopoletin in significant quantities, a molecule whose powerful MAO-inhibitory property was recently discovered. Their addition to ayahuasca is therefore deliberate. It should be noted that Brunfelsia species are frequently added to the jurema brews, which are processed with the bark of certain species of Mimosa, thus facilitating the absorption of the high concentrations of DMT present in these Brazilian entheogenic drinks.

A vast set of plants added to the ayahuasca/yagé acts differently, it does not reinforce a pre-existing effect but confronts or clashes with the effect of the mother brew, up to influence it in various ways. It is the most interesting collection of plants for us Westerners, which we could call modulating additives, and unfortunately it is also the one we know little more than a list of dry botanical or popular names.
A group of these modulating plants concerns species from the Solanaceae family; the best known is toé (Brugmansia), which produces hyoscyamine and other tropane alkaloids. The tropanic solanaceous plants, to which jimsonweed, mandrake, and belladonna also belong, are the “witchcraft” plants par excellence, difficult to handle, to interpret their visionary message, difficult to not be “bewitched” by them.

In some isolated Amazonian contexts, lesser-known species are added, such as Iochroma fuchsioides (guatillo). This shrub almost certainly produces the tropane alkaloids present in the toé , and we know that in the Sibundoy, its leaves and its bark are used as a hallucinogen per se. The addition of tropanic plants is always a dangerous operation, which only the scrupulous vegetalistas know how to handle, and decisively changes the quality of the visionary experience. How much the content of the ayahuasca visions is only influenced or literally overwhelmed by the tropane component, apart from being certainly a question of dose, is more a question of individual reactions than of pharmacology. I have the impression that to the most intimate part of the knowledge of the interaction of ayahuasca with tropanic plants, we Westerners have not yet been allowed to access them.
For some plants, although knowing only the botanical or traditional names, and in different cases not even knowing which part of the plant is added to the ayahuasca/yagé brews, we can receive indirect indications about their psychoactive potential by observing the knowledge we have about species of the same genera.

The hiporuru (Alchornea castaneifolia), a Euphorbiaceous plant which in the Iquito area is added to ayahuasca, is considered one of the “master plants.” We know other Alchornea species used as intoxicant, and the strongest analogy is with the African species A. floribunda and A. hirtella, whose roots are used as entheogenic visionary sources in an ancestor cult, the Byeri, among the Fang and other Bantu populations of Western Equatorial Africa (Gabon and neighboring regions). In the initiatory rite byeri the strong dose of ingested alan (A. floribunda) induces in the adept a profound vision, through which and through the skulls of the deceased relatives who are shown to him, comes into contact with the ancestral spirits to directly receive the ultimate knowledge of the belonging clan. It is possible that hiporuru produces the same alkaloids as these African congeners, the alchorneines, and that the most active part of the plant concerns the root.
Regarding the addition of armaciza (Erythrina poeppigiana), it is appropriate to consider the numerous cases in which the seeds of species of the genus Erythrina, albeit with their intrinsic toxicity, are involved as intoxicant sources. For example, in Guatemala the seeds of E. flabelliformis are ingested by shamans to allow communication with spirits.
The addition, in the Peruvian area of Iquito of uchu-sanango, a species of Tabernaemontana, is interesting, since we know that this genus produces alkaloids from the ibogaine group, and it would therefore be an ethno-psychopharmacological “first encounter,” albeit indirect, among the active principles of the Amazonian ayahuasca with those of the African iboga, the famous visionary plant of the Bwiti religious cult.
A small group of plants is added to ayahuasca to change its flavor, and we could consider them as organoleptic additives. This is the case of kana (Sabicea amazonensis), which in Vaupés is added to the yagé to make it sweet rather than bitter.
But the number of plants added to ayahuasca is much more extensive, as is our ignorance in this regard. What about the toé nero, botanically identified as Teliostachia lanceolata var. crispa, whose leaves are also used alone as an intoxicant; or of bobinsana (Calliandra angustifolia), whose roots are used as a stimulant in the Rio Pastaza (one drinks the decoction before facing a physical effort such as swimming); or of remo caspi (Pithecellobium laetum), which some vegetalistas claim strengthens ayahuasca to the point that it can leave the experimenter unconscious for 12 hours? A treasure of shamanic knowledge accumulated in the centuries-old activity of “research around a pot and its contents,” which, as yet another gift of shamanism, could become a psychopharmacological treasure for Western culture, with good prospects of knowledge acquisition in terms of new molecules of future medicinal, spiritual, and social importance.