Symptoms
Addiction or harmful habbits Anxiety or worry Difficulty focusing Feeling disconnected from others Lack of energy or motivation Sadness or low mood
Substances
Psilocybin

Synthesis Institute

Provider type Retreat center
Location Netherlands
Synthesis Institute

The Synthesis Immersion Retreat is a legal, professionally guided psilocybin retreat program based in the Netherlands, framed as a seven week journey of preparation, a five day retreat, and integration. It is designed for personal growth, expanded self awareness, emotional insight, and new ways of being, not for diagnosis or treatment of mental health conditions. The program combines research informed best practices with wisdom traditions, rituals and spiritual practices to create a structured group container that can catalyze lasting change.

Service

Immersion is a three part experience: three 75 minute online preparation sessions in the weeks before the retreat, a five day residential retreat at New Eden in the Netherlands with two psilocybin ceremonies, and three 75 minute online group integration sessions afterwards. The on site program includes intention setting, guided ceremonies with truffles or mushrooms in an optimised setting, live music, meditation, breathwork, workshops, and one to one meetings with facilitators. Group size is limited to about 15–20 participants, with a high facilitator to participant ratio and an emphasis on community and shared process.

Safety

Synthesis positions Immersion as a legal and carefully held psychedelic group retreat using psilocybin containing truffles in the Netherlands and, in some formats, mushrooms in Costa Rica. Safety and readiness are described as top priorities. Every participant completes a health pre screener and a comprehensive health screening, with clear exclusion criteria that include suicidal thoughts or attempts, psychosis, schizophrenia, certain personality and dissociative disorders, and self destructive behaviour. The program explicitly states that it is not intended to diagnose or treat mental health disorders. Ceremonies are facilitated by an experienced team, with approximately one support staff member for every two to three participants.

Care pathway

Prospective participants are invited to start with a short readiness quiz or a free discovery call, then submit an online health pre screener. If suitable, they pay a refundable deposit and complete full medical and psychological screening before being approved. Once enrolled, they join three online preparation sessions, attend the five day retreat at New Eden with two ceremonies and structured daily schedule, and then take part in three online integration sessions focused on somatic, social, and ongoing life integration. Throughout, the emphasis is on community, clear intention, and translating insights into everyday change.

This description was generated based on information from the official website and other materials provided by the provider.

Symptoms Treated

Addiction or harmful habbits Anxiety or worry Difficulty focusing Feeling disconnected from others Lack of energy or motivation Sadness or low mood

Substances

Psilocybin

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