A Retrospective Effectiveness Trial of Ketamine-Assisted Psychotherapy in Adult Patients Coping With Mental Health

Inclusion Criteria: * Written informed consent * Over the age of 18 * Should be psychologically and medically cleared by a psychiatrist, family physician, or treatment team * Diagnosed with Major Depressive Disorder (MDD), Bipolar Depression, Generalized Anxiety Disorder, Obsessive Compulsive Disorder (OCD), and Eating Disorder by a licensed healthcare practitioner (including Field Trip Consultants) * A significant history of trauma and/or formal diagnosis of PTSD as per the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM 5) * Individuals who have received Electroconvulsive Therapy (ECT) or other neuromodulatory treatments like Transcranial Magnetic Stimulation (TMS) * Individuals reporting suicidal ideation may be included, as suicidal ideation is a symptom of a Major Depressive Episode (MDE) Exclusion Criteria: * Individuals who are unable to consent to the treatment * Pregnant women and nursing mothers --Note that Post Partum Depression (PPD) can be considered on a case-by-case basis in consultation with the National Medical Director. * There is a relative (not absolute) contraindication for individuals with a Body Mass Index (BMI) of above 35. These clients must be given thorough consideration by the medical team. * Any individual who has met DSM 5 criteria for a Substance Use Disorder in the past 3 months. * Note that patients with alcohol, opioid, benzodiazepine, cocaine, and amphetamine use disorders need to go through detox (for alcohol/benzodiazepines) and be sober for 4 weeks. * Note that mild active alcohol, cocaine, and cannabis use can be considered on a case-by-case basis at the comfort level of the treatment team if the client has demonstrated abstaining or significant reduction of use prior to starting treatment. * Daily use of moderate to high doses of benzodiazepines * Individuals who are experiencing psychotic symptoms as part of an MDE (mood congruent/ mood incongruent) * Psychosis: Schizophrenia, Schizoaffective disorder, Bipolar 1 with psychotic features during mania * Active Mania: Bipolar 1 (chronic non-disruptive hypomania is an exception at the discretion of the consultant) * Borderline Personality Disorder * Uncontrolled medical disorders * Physical conditions with negative interaction with ketamine (e.g., metabolic blood disorder) * Individuals with symptomatic acute brain injury within 90 days of serious injury * Individuals diagnosed with moderate to severe sleep apnea * Individuals who are unable to identify a person or service to assure their safe transport to home post treatment