SSRI Administration to Reduce Acute Stress Disorder Symptoms and Prevent Depression and PTSD in Physical Trauma Victims

Inclusion Criteria: * Male or female outpatients at least 18 years of age with a primary (the condition that is most central to the patient's current distress) symptoms of Acute Stress Disorder as defined by DSM-IV criteria: A1, A2 and at least one additional category of Acute Stress Disorder symptoms (i.e., B, C and or D criteria). * Patients must have had a medical trauma (even if fully resolved or minor) within the prior 3 weeks resulting in admission to the emergency room and/or inpatient hospital as part of their acute trauma resulting in ASD symptoms. Exclusion Criteria: * Patients will be excluded from entry into the study for current serious medical instability such as hemodynamic compromise, or serious head injury resulting in impaired mental status. Patients with a history of medical instability associated with their traumatic injury will be allowed study entry once the problem has resolved (as long as resolves within 3 weeks of trauma as per inclusion criteria). * Patients with a trauma resulting in head injury related seizures, or with epilepsy (except a prior history of febrile seizures of infancy which are not exclusionary). * Pregnant or lactating women or those of childbearing potential not using medically accepted forms of contraception will be excluded. * Concurrent use of other antidepressants, with the exception of trazodone \< 100mg/day for sleep, or amitriptyline in doses ≤ 50 mg daily for pain. Patients may remain on concomitant benzodiazepines (\<2 mg/d clonazepam or its equivalent), or sleep aids (i.e., trazodone, zolpidem (Ambien), zaleplon (Sonata)) as long as the drug therapy was initiated at 1 week prior to randomization; the dose will be held constant through the study, and will be controlled for in the analysis. * Lifetime diagnosis of schizophrenia or any other psychosis, mental retardation, organic mental disorders, bipolar disorder; obsessive-compulsive disorder, eating disorders, cutting or other significant self-injurious behavior, or alcohol/substance abuse disorders within the last 3 months are study exclusions. Patients with a current primary diagnosis of major depression, dysthymia, social anxiety disorder, panic disorder, and generalized anxiety disorder are excluded; thus, the presence of these disorders is permissible as long as the ASD symptoms constitute the predominant symptomatology. * Patients with a history of hypersensitivity or prior poor response to escitalopram are excluded. * Concurrent dynamic or supportive psychotherapy is permitted as long as it has been ongoing for at least 1 month prior to onset of study entry. * Patients with a positive toxicology screen at baseline consistent with evidence of current substance abuse or dependence as determined by clinical interview.