Trial of Mifepristone in Combat Veterans With Posttraumatic Stress Disorder

Inclusion Criteria: * Subject is a male U.S. veteran * Subject was exposed to combat or another criterion A traumatic event during military service * Subject meets diagnostic criteria for chronic PTSD Exclusion Criteria: * Veteran has a history of adrenal insufficiency or a plasma cortisol level less than 5 mcg/dl at screening * Veteran has a moderate-severe traumatic brain injury, a history of a stroke, or another neurological illness or injury likely to impact cognitive functioning * Veteran has diabetes mellitus, an endocrinopathy, or another major medical illness. * Veteran is taking oral corticosteroids * Veteran has a lifetime diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder * Veteran is currently suicidal or otherwise is in need of urgent clinical care * Veteran is currently receiving specialized trauma-focused psychotherapy (i.e., prolonged exposure, cognitive processing therapy or eye movement and desensitization reprocessing). * Veteran is not willing to use effective means of birth control during the study or for 90 days after taking study medication * Veteran has history of allergic reaction to mifepristone