Add-on Buprenorphine at Analgesic Doses for the Treatment of Severe Suicidal Ideas During a Major Depressive Episode

Inclusion criteria

• The patient has been correctly informed.
• The patient must have given his/her informed and signed the consent form.
• The patient must be insured or beneficiary of a health insurance plan.
• The patient is at least 18 years old and 65 years old at the most.
• The patient is hospitalized or followed in consultation.
• The patient has a current major depressive episode without psychotic features according to the criteria of the "Diagnostic and Statistical Manual of Mental Disorders"
• The patient has a score \> 20 of the "Montgomery-Asberg Depression Rating Scale".
• The patient has a current Scale for Suicidal Ideation (SSI) score \> 8.

Exclusion criteria

• The patient is participating in another interventional trial;
• The patient is in an exclusion period determined by a previous study;
• The patient is under judicial protection, or is an adult under guardianship;
• The patient is under compulsory admission;
• The patient refuses to sign the consent;
• it is impossible to correctly inform the patient.
• The patient is pregnant or breastfeeding.
• The patient suffers from schizophrenia;
• The patient suffered from moderate to severe alcohol use disorder or substance use disorder (except tobacco and caffeine) over the last 12 months according to DSM-5 criteria ;
• The patient currently suffers from severe and/or unstable medical condition (including severe respiratory or hepatic insufficiency) or a painful medical condition;
• The patient has a current known sleep apnea.
• The patient currently takes analgesic treatment (including Nonsteroidal anti-inflammatory drug and paracetamol);
• The patient currently takes central nervous depressant drugs at sedative doses (based on the investigator's assessment), including benzodiazepines, antihistamines, and sedative antipsychotics;
• The patient currently takes major CYP3A4 Inhibitors and inducers;
• The patient currently takes has received Electroconvulsivotherapy over the last 3 months.