Ketamine Infusion for Symptomatic Improvement in Severe Borderline Personality Disorder

Inclusion Criteria: * Adult patient aged 18 to 65 years * Fluent in French * Person affiliated with or receiving social security benefits. * Diagnosis of borderline personality disorder established according to the DSM-5 MINI criteria (5 out of 9 criteria) * Severe borderline personality disorder * Patient receiving stable pharmacological (antipsychotic, mood stabilizer, antidepressant) and/or non-pharmacological (schema therapy, DBT) treatment for four weeks Exclusion Criteria: * Personal history of an acute psychotic episode or chronic psychotic disorder * Personal history of a manic or hypomanic episode * Family history (first-degree relatives) of a psychotic disorder * Current severe depressive episode * Recreational ketamine use (multi-weekly ketamine use) * New long-term treatment introduced within the previous four weeks (antidepressant, antipsychotic, mood stabilizer) * Prescription of an Monoamine oxidase inhibitors (increased risk of hypertension) * Specific absolute contraindication to ketamine * History of cirrhosis or major liver function test abnormalities * Major ECG abnormality