Effects of Escitalopram on Autonomic Reactivity in Post Traumatic Stress Disorder in Veterans of Operation Enduring Freedom and Iraqi Freedom

Inclusion Criteria:

- Inclusion Criteria - Group I

- Patients, men and women between 19 and 55 years of age, inclusive.

- Patients with diagnosis of Posttraumatic Stress Disorder as determined by
Mini-International Neuropsychiatric Interview (M.I.N.I.).

- Patients, who are able to comprehend and satisfactorily comply with protocol
requirements and have an ability to read and write English.

- Patients, who signed the written informed consent given prior to entering any study
procedure.

- Inclusion Criteria - Group II

- Patients, men and women between 19 and 55 years of age, inclusive.

-Patients with diagnosis of Major Depression as determined by Mini- International
Neuropsychiatric Interview (M.I.N.I.). A diagnosis of PTSD will be exclusionary.

- Patients, who are able to comprehend and satisfactorily comply with protocol
requirements and have an ability to read and write English.

- Patients, who signed the written informed consent given prior to entering any study
procedure.

Exclusion Criteria:

- History of cardiovascular disease or a history of hypertension.

- Patients with a concurrent DSM-IV diagnosis in any of the following categories as
determined by the M.I.N.I.

- Lifetime Schizophrenia and Schizoaffective Disorder

- Lifetime Bipolar I Disorder

- Substance Dependence or Abuse (excluding nicotine) within one month prior to the
Screening Visit.

- Patients with a history of intolerance or hypersensitivity to escitalopram or
citalopram.

- Patients who based on history or mental status examination have a significant risk of
committing suicide. Current suicide risk (past month) will be assessed using the MINI
Suicidality Module. Subjects considered at high suicide risk based on the module (>
17 points) will be excluded from study participation.

- Patients who are homicidal or violent and who are in the Investigator's opinion in
significant imminent risk of hurting others.

- Subjects will be excluded who have a history of significant medical illness and who
are on medications that affect cardiac and/or autonomic function.

- Female patients who are pregnant, planning to become pregnant, or if of childbearing
potential, not using an acceptable method of birth control.