Primary investigator left VA employment

In this study, the investigators are looking at how PTSD affects things such as memory, attention, reaction to sounds, eye movements, and heart rate. The investigators are also studying whether a medication called prazosin has an effect on these things.

Converging lines of evidence suggest that central nor adrenergic function is perturbed in PTSD. Placebo-controlled trials demonstrate that the centrally acting alpha-1 antagonist prazosin is clinically effective for several core symptoms of PTSD in combat veterans. However, no detailed assessment of the impact of prazosin on human neurophysiology and cognition have been conducted. Our hypotheses are based on studies that demonstrate (1) the importance of central adrenergic receptors in regulating fundamental neurophysiologic and cognitive functions, (2) the alteration of these functions in PTSD, and (3) the efficacy of prazosin in improving the clinical symptoms of PTSD. The primary objective of this study is to measure the subtle neurocognitive and neurophysiologic effects on prazosin in combat veterans with PTSD.

Inclusion Criteria:

• Exposure to one or more life-threatening war zone trauma events;
• DSM-IV diagnosis of PTSD derived from the Clinician-Administered PTSD Scale (CAPS), CAPS total score greater than or equal to 50;
• CAPS recurrent distressing dreams item score greater than or equal to 5 (of a maximum score of 8), with a frequency rating greater than or equal to 2 (of 4);
• stable dose of non-exclusionary medications and psychotherapeutic treatment for at least 4 weeks prior to randomization;
• good general medical health;
• female participants must agree to use a reliable form of birth control throughout study.

Exclusion Criteria:

• Acute or unstable chronic medical illness;
• diagnosis of current schizophrenia, schizoaffective disorder, psychotic disorder not otherwise specified, bipolar disorder, delirium, or cognitive disorder;
• severe psychiatric instability or severe situational life crises;
• substance dependence disorder currently or in past 3 months;
• current cocaine or stimulant abuse or evidence of acute intoxication on alcohol or nonprescribed medication;
• allergy or previous adverse reaction to prazosin or other alpha-1 adrenergic antagonists;
• serious head injury with loss of consciousness of greater than 30 minutes;
• current diagnosis of seizure disorder;
• current use of prazosin or other alpha-1 adrenergic antagonists;
• current use of atypical antipsychotic medication;
• stimulants or alternative medications with stimulant properties (e.g. ephedra), certain exposure therapies must be completed at least 4 weeks before baseline;
• certain medications (trazodone, erectile disfunction medications) are not allowed or are restricted during the study;
• women must not be pregnant or nursing during the study.