Medicine × Mystery × Initiation
Ayahuasca
The Mother. The Serpent. The Vine of the Soul.
She does not show you what you want to see.
She shows you what the body has been holding without permission.
Origins · Pharmacology · Neuroscience · Ethics of Engagement
Born in the heart
of the Upper Amazon.
Ayahuasca originates in Western Amazonia — a brew most classically prepared from the liana Banisteriopsis caapi and the leaves of DMT-containing plants such as Psychotria viridis or Diplopterys cabrerana. Ethnobotanical documentation places its use among dozens of Indigenous groups: the Shipibo-Konibo, Ashaninka, Kichwa, Shuar, Tukanoan, and Panoan-speaking peoples, across the Upper Amazon, Orinoco Basin, and Pacific lowlands of Colombia and Ecuador.
Western science documented it in the 19th century — but oral histories and archaeological evidence suggest a far older Indigenous usage, woven into the fabric of healing, divination, community regulation, cosmological education, and initiation for thousands of years before any botanist arrived.
"Ayahuasca is not a drug. She is a sentient plant teacher with her own intentionality, personhood, and agency — a living intelligence that has guided healers long before it was given a name in any Western language."
— Shipibo-Konibo oral traditionAyahuasca has since diffused from its Indigenous matrices into mestizo curanderismo in Peru, Brazil, Colombia and Ecuador; into Brazilian ayahuasca religions (Santo Daime, União do Vegetal, Barquinha); and more recently into a global network of retreats and urban circles — a diffusion that carries immense ethical weight, which we will address directly.
The architecture
of sacred work.
Key elements are consistent across traditions — not because one borrowed from another, but because the medicine itself seems to require certain conditions to be held safely.
Night-time ceremony
Ceremonies are held at night, led by experienced healers — often in a maloka or communal structure. Darkness is not aesthetic; it is functional. The reduction of external stimuli allows the medicine's visual and somatic language to dominate.
Icaros — sacred songs
Icaros are the songs of the medicine. Healer-specialists use them to guide, protect, and modulate the experience — calling specific healing currents, working with participants' processes, and maintaining the integrity of the ceremonial space. The voice is a tool.
Dietas
Dietary and behavioral restrictions before, during, and after ceremonies sensitize perception and cultivate relational depth with plant spirits. Dieta is not restriction — it is a form of listening. The body is prepared to receive what the medicine carries.
Ritual purging
Vomiting, sweating, and emotional purging are understood as physical and energetic cleansing — not side effects to be managed but integral to the healing. The body completes what the mind cannot fully articulate.
The visionary
landscape.
Ayahuasca visions consistently feature serpents, jaguars, anacondas, birds of prey, celestial beings, and geometric lattices. These are not random hallucinations — they are recurring symbols that appear across cultures, continents, and centuries of contact with this medicine.
In Shipibo cosmology, the anaconda is the mother of the rivers — the jaguar her guardian. Many lineages interpret serpent and jaguar visions as direct encounters with the spirit of the medicine itself. From a Jungian frame, these images represent deep collective archetypes: the serpent as life/death/renewal; the jaguar as shadow, power, and courage.
The geometric lattices are significant. Kene designs — the intricate geometric patterns made by Shipibo women in textiles — are reported to be direct transcriptions of what is seen in ceremony. Vision, sound, and pattern interweave in Amazonian ontology into a unified language that precedes words.
Life, death, and renewal. Kundalini energy. The mother of rivers. The first teacher of the healing songs.
Shadow, power, and courage. The warrior guardian. The gatekeeper between worlds who tests and protects those who enter.
The geometric fabric underlying reality. The kene made visible. What quantum physicists and Shipibo weavers describe in the same breath.
What the vine
does to the brain.
Ayahuasca is a pharmacologically complex mixture whose effects emerge from the synergy of two compound families. DMT (N,N-dimethyltryptamine) from Psychotria viridis is a potent psychedelic tryptamine acting primarily as a partial agonist at 5-HT2A and 5-HT1A receptors, with additional activity at sigma-1 receptors.
Harmine, harmaline, and tetrahydroharmine — the primary alkaloids in B. caapi — are reversible monoamine oxidase A (MAO-A) inhibitors. They prevent gut and hepatic breakdown of orally ingested DMT, rendering it psychoactive. Without the vine, the leaves produce nothing. The synergy is not accidental — it is the whole point.
DMT reaches peak plasma concentrations approximately 1.5–2 hours after ingestion, with psychoactive effects lasting 4–6 hours. Harmine and beta-carbolines also modulate 5-HT2A/2C receptors, interact with dopamine and adrenergic systems, and — in preclinical models — appear to promote neurogenesis and neurotrophic signalling.
What we can now
measure and see.
Modern neuroimaging has begun to confirm what indigenous traditions knew empirically: something real and profound happens in the brain during ayahuasca ceremonies. A 2026 mega-analysis of psychedelic neuroimaging found a shared neural fingerprint across substances — including ayahuasca — characterised by:
Posterior cingulate thinning
Repeated ayahuasca use is associated with cortical thickness alterations in midline structures — particularly thinning of the posterior cingulate cortex, a key hub for self-referential thought. Long-term structural change, not just acute effect.
Global connectivity increase
Increased global brain connectivity, reduced modular segregation, and disrupted coupling between blood flow and neuronal activity. Brain regions that normally don't communicate strongly begin to exchange information — the neural basis of expanded perception.
Resilience & well-being
Long-term ayahuasca users show altered functional connectivity in regions related to emotional processing, theory of mind, and embodied self — with some studies linking these changes to increased resilience, compassion, and well-being.
Increased brain entropy
Acute administration increases cortical excitability, brain entropy, and desynchronization of canonical networks. The ordered, predictive brain temporarily enters a more flexible, less constrained state — a measurable analogue of what tradition calls "the opening."
What the trials say.
Ayahuasca shows rapid and often sustained antidepressant and anxiolytic effects in carefully screened populations. The evidence base has grown significantly in the last decade.
Large, rapid decreases in MADRS depression scores within 24 hours of a single dose in treatment-resistant major depression. Effects sustained at 7 days and beyond.
Recent European Phase IIa studies of ayahuasca-inspired DMT-harmine combinations report significant reductions in depressive symptoms versus placebo, with effects lasting several weeks after a single administration.
Meta-analyses pooling data across classic psychedelics report robust short-to-medium-term improvements in depression and anxiety, with acceptable safety profiles in controlled therapeutic settings.
Studies of Indigenous-led retreat contexts show improvements in psychological distress, existential well-being, and quality of life — particularly in participants who complete preparation and integration work.
Sources: Palhano-Fontes et al. 2019; Frontiers 2023, 2026; Oslo Trial 2024; Goldberg et al. 2022; NatureMed mega-analysis 2026. This is not medical advice.
This medicine belongs
to someone.
Ayahuasca has diffused from its origins into a global market. That diffusion brings immense opportunity — and immense responsibility. The traditions that hold these lineages are living. The communities are vulnerable. The plants are under ecological pressure. None of this can be separated from how we engage.
Every retreat I support contributes materially to the communities who host us. Preparation is mandatory — not because I impose it, but because the medicine itself demands it. Integration is built into every journey before departure, not offered as an afterthought. Reciprocity is not an optional extra. It is the foundation on which this work stands.
Ceremonies held
in their territories.
Each offering listed here is held by practitioners who work in full integrity with both the medicine and the territory where ceremonies are held. Every container includes deep screening, preparation, and integration support — structured and delivered by Rosa F. Brissos, PhD — before and after every journey.
Yawanawá Immersion
Aldeia Nova Esperança, Acre.
A 10-day immersion in Yawanawá territory, held in Aldeia Nova Esperança, Acre, Brazil.
This is not a retreat product dressed in Indigenous aesthetics. It is a cultural exchange built on relationship — a doorway into the forest, the songs, the medicines, the stories, and the living rhythm of one of the Amazon's most intentional communities.
Aldeia Nova Esperança is led by Chief Iskukua Biraci Jr., guardian of one of the largest villages in the Yawanawá community. The village sits deep inside Indigenous territory, around seven hours into the forest — far from urban influence, modern noise, and the diluted version of "medicine work" that often circulates outside its source.
Here, the forest is not background.
It is the field. The teacher. The nervous system of the experience.
This immersion offers the possibility to learn directly from the Yawanawá lineage through ceremony, song, traditional painting, sacred plants, forest walks, community sharing, ancestral stories, and daily life in the village.
The invitation is not to consume a culture. It is to enter with humility, preparation, and respect — knowing that this work belongs to a people, a territory, a history, and a living spiritual technology that cannot be separated from the land that carries it.
Rosa F. Brissos, PhD, supports this experience through deep preparation and integration, bringing trauma-attuned, nervous-system-informed guidance before and after the immersion.
Because entering the forest is only one threshold.
The deeper work is how you prepare your body, mind, and spirit before you arrive — and how you metabolize what the forest shows you when you return.
- End of November 2026 · 10-day full immersion
- Aldeia Nova Esperança · Yawanawá Territory · Acre, Brazil
- Ceremony, medicine plants, song, forest life, and cultural exchange
- Trauma-attuned support team on-site
- Rosa's preparation and integration program included
- Deep prior preparation required · offered when timing, relationship, and readiness are right
This is not for people looking for an exotic experience.
It is for those who understand that real medicine work asks for reverence, maturity, and reciprocity.
Yawanawá Immersion
Interest is held until timing is right — which can be a year or more. This is not a booking system. It is an expression of sincere intention.
European Ceremonial
Containers.
For many people, the call to medicine work arrives before the possibility of travelling across the world. Some are caring for families. Some are navigating demanding professional lives. Some need the familiarity of European ground beneath their feet while entering the unfamiliar terrain of the psyche, the body, and the soul.
This is why we are developing small, carefully held ceremonial containers in legally permissive European contexts, with facilitators who meet a high standard of ethical practice, preparation, and lineage relationship.
These are not drop-in ceremonies. They are not psychedelic tourism. They are not experiences built around intensity for the sake of intensity. They are structured, selective, trauma-aware spaces for people who are ready to meet the medicine with respect.
Every collaboration is chosen with care. The practitioners we work with are expected to maintain an active personal relationship with the medicine, engage in supervision, continue their own inner work, and remain connected to the people, territories, and traditions from which their lineages come.
Where possible, elders and traditional knowledge holders are invited to Europe to share directly from their own lineages, carrying decades of lived relationship with these plant teachers.
Our role is not to extract wisdom and repackage it. Our role is to build bridges with integrity — between ancestral knowledge and modern nervous system science, between ceremony and preparation, between revelation and integration, between the sacred and the practical life that waits for you afterward.
When these retreats become available, information is shared privately with people who have been screened, prepared, and assessed for fit. If you already know this is the kind of work you are seeking, contact us directly to express your interest.
European Ceremonies Waitlist
Dates are released to those on the list first. No commitment required — only sincere intention.
Request a Private
Group Program.
If you are enquiring on behalf of a company, organization, private community, cultural group, or group of friends, you can request a tailored retreat or specialized program here.
These private containers are designed for groups that need more than a standard retreat format — whether the focus is productivity, longevity, leadership, nervous system resilience, emotional repair, cultural belonging, trauma-aware support, or a deeply intentional shared experience.
Rosa F. Brissos, PhD, and her collaborators create programs with careful preparation, cultural sensitivity, trauma-attuned facilitation, and respect for the specific needs of each group.
Use the form below to request available dates, package information, pricing, or a custom proposal.
Bring Your Group
Tell us about your group, your needs, and what you are looking for.
Ready to go
into the forest?
All journeys begin with preparation. Whether you are considering the Yawanawá immersion or European ceremonies, the first step is the same: knowing you are ready.