Ayahuasca, Esketamine and Premenstrual Symptoms

This randomized, double‑blind trial (n=20) will assess the effects of a single oral dose of ayahuasca versus oral esketamine on the menstrual cycle and premenstrual symptoms in healthy women aged 18–65, with the primary outcome measured by the Premenstrual Symptom Tracking Instrument (PSST) from enrolment to three weeks. Participants will be allocated in a parallel design to an experimental arm receiving oral ayahuasca or an active comparator arm receiving oral esketamine under double‑blind conditions. The study is described as basic science, enrols healthy female volunteers without psychiatric or other medical comorbidities, has estimated enrolment of 20, and is scheduled to start on 20 December 2025 with completion anticipated in July 2026.