Ketamine and Epigenetic Aging

Inclusion Criteria: * Be 18-64 years old of any sex, gender orientation, and ethnicity * Read, understand, and provide written informed consent in English, * Meet criteria for a primary psychiatric diagnosis of Major Depressive Disorder (MDD) or Post-traumatic Stress Disorder (PTSD) for greater than 4 weeks, * Have a history of at least 1 failed medication trial targeting MDD or PTSD * Have a reliable form of transportation to lodging or home following the completion of each ketamine infusion treatment day, * Be generally healthy, as assessed by medical history, physical examination (including vital signs), and clinical laboratory evaluations, * Be of non-childbearing potential or utilizing an acceptable form of birth control (females-only) * Report a pre-treatment symptom level of ≧15 on the PHQ-9 or ≧ 33 on the PCL-5 * Consent to participation in venipuncture, drug test, pregnancy test (for females) psychiatric evaluation, rating scale completion and ketamine infusion treatment series of six over the course of two to three weeks. Exclusion Criteria: * Delirium or dementia diagnosis, * Unstable medical illness or clinically significant laboratory results, * History of clinically significant cardiovascular disease or electrocardiogram (EKG) findings, or medical conditions that put the patient at high risk for possible cardiac side effects, or uncontrolled hypertension * History of multiple adverse drug reactions, * Current or past history of psychotic disorder or psychotic symptoms, * Current manic symptoms, * Active substance use disorders with the exception of nicotine and caffeine, within the past six months or any past history of ketamine or PCP abuse, * Requirement of excluded medications that interact with ketamine, * Pregnancy, breastfeeding or unacceptable means of birth control in a female of child-bearing age, * Current acute suicidal or homicidal risk, * Previous exposure to ketamine