Esketamine is approved as treatment for TRD, a syndromic diagnosis whose etiopathogenesis is varied and frequently concurrent with comorbid psychiatric diagnoses. The dissociative symptoms and hallucinations occasionally observed with esketamine are considered adverse effects. However, this may offer psychotherapeutic opportunities for patients affected by severe psychological trauma. We present a single-case study of a 45-year-old cloistered nun, prescribed with esketamine treatment for TRD, who re-experienced intense and severe traumatic experiences at each application of the drug, requiring specific psychotherapeutic intervention. 

Possible severe trauma due to child sexual abuse was identified in the clinical interview prior to the indication of esketamine. Depression measurement scales, analog scales, and thorough qualitative data collection on the phenomenology of the experience presented by the patient were used. Trauma flashbacks appeared during the first application of the drug, requiring added psychotherapeutic accompaniment session (Acceptance and Commitment Therapy, ACT), in preparation, intake, and integration, following Psychedelic-Assisted Therapy models. Coping tools adapted to her religious condition were offered for a mystical and hallucinatory experience that included Christian symbols and monsters with the final subjective result of "trauma release". ACT-derivated techniques enabled her to modulate and contain the traumatic memories, impacting significantly in her clinical process. Beyond the favorable response of depressive symptomatology, the present case illustrates how esketamine effects considered adverse (dissociation and hallucinations) may offer therapeutic opportunities. Given the varied nature of TRD, this possibility could be contemplated in cases associated with other psychiatric diagnoses.