Oral Ketamine-Assisted Psychotherapy Leading to Prolonged Remission in Recurrent Dissociative Neurological Symptom Disorder With Mutism: A Case Report

Dissociative neurological symptom disorder (DNSD), termed functional neurological symptom disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR), presents with neurological symptoms not explained by structural disease.The first line treatment of DNSD is psychotherapy, but when the conflict maintaining the symptoms cannot be put into words, psychotherapy often stalls.This report describes a 56-year-old woman with a four-year history of episodic loss of consciousness and progressive speech loss, with normal neurological investigations.Escitalopram, intravenous ketamine infusions given without psychotherapy, and venlafaxine produced no meaningful benefit.A 30-day inpatient program of psychotherapy, family therapy, and speech therapy restored her speech, but she relapsed into complete mutism four months after discharge, and no stressor could be identified.A lorazepam-assisted interview produced sedation without speech.She then received six alternate-day sessions of oral ketamine-assisted psychotherapy, titrated from 50 mg to 150 mg, within a psychodynamically informed frame; while venlafaxine 225 mg/day was continued and family therapy was delivered alongside.She spoke a few words in the third session (100 mg) and conversed spontaneously in the fourth (150 mg), describing a conflict between a rigid moral self-image of never being greedy and unspoken distress over a family property dispute.Speech has been sustained for more than one year, and all psychotropic medication has since been withdrawn.The report proposes that, this single case is hypothesisgenerating.It suggests that ketamine may be a useful and a better abreactive agent in selected patients with treatment-resistant DNSD, and that the therapeutic frame is also essential for the improvement to happen, and further controlled comparison with benzodiazepine-assisted interviews is warranted in the future.