Combined Ketamine and eCBT Intervention for PTSD

Inclusion Criteria: * Diagnosis of PTSD by a psychiatrist on the team using the Clinician Administered PTSD Scale (CAPS-5) with a score of at least 50 and a medium presentation. * Patients will have received at least 2 different types of prior treatment, both of which produced less than a 50% reduction in the participant's symptoms. * Participants with hypertension or cardiovascular disease must be receiving stable treatment to participate. * Participants must speak and read English, and will have consistent and reliable access to the internet. * Patients with suicidal ideation will be included. * Patients with a history of substance abuse will be included (except for opioid use disorder). Exclusion Criteria: Hypomanic/manic episodes, bipolar disorder, acute psychosis, opioid use disorder, treatment with Naltrexone, pregnancy, postpartum, breastfeeding, untreated hypertension, cardiovascular disease, ASPD, active homicidal ideation, and general noncompliance with the study protocol.