Predicting Responses to PTSD Treatment With Iris and Cardiovascular Tests
Predicting Responses to PTSD Treatment With Iris and Cardiovascular Tests
Posttraumatic stress disorder (PTSD) affects many individuals who experience a traumatic
 event. There are a variety of treatment options for PTSD, including psychotherapy (talk
 therapy) options, as well as medications, such as the drug prazosin. Each of the treatment
 options available is effective at significantly reducing the symptoms of PTSD in some, but
 not all, individuals with PTSD. However, investigators are not yet able to predict in advance
 who is likely to respond to which of the available treatments. Neither are the investigators
 able to explain what changes in the brain after exposure to a traumatic stressors, and why it
 results in persistent symptoms of PTSD for some people, but not for others.

 In this study, the investigators are testing two things: First, is testing whether two
 simple, easy tests of how an individual's blood pressure changes with standing and how an
 individual's eye reacts to a pulse of light may be able to predict whether that person is
 likely to respond to the medication prazosin for PTSD. Second, is testing whether those who
 have been exposed to a traumatic stress show differences in how their body regulates the
 response to the stress-signal noradrenaline.
Enrollment is currently paused due to COVID-19

 In this study, individuals will undergo an assessment that includes taking a history of their
 previous exposure to traumatic events, an assessment of current mental health symptoms
 including those associated with PTSD, and an assessment of physiologic measures, such as
 blood pressure and pupillary responses to light. For individuals who have current symptoms of
 PTSD and for whom use of the medication prazosin is a reasonable and safe option, a second
 phase of the study will be offered. In this second phase, how the individual's PTSD symptoms
 change when taking prazosin will be assessed. In addition, to test whether any changes are
 related to the prazosin itself or are part of a placebo effect, the individual will be
 randomly assigned to periods where he or she is taking a pill that looks like prazosin but is
 actual placebo (a pill with no active ingredient), and periods where he or she is taking a
 pill that looks the same but this time is actual prazosin.
Inclusion Criteria:

 -  Veteran of the U.S. Armed Forces

 -  Current diagnosis of PTSD (as documented in clinical chart and/or per participant
 report; a rule out diagnosis from a VA provider accompanied by a referral to the VA
 PTSD Outpatient Clinic (POC) will also be considered sufficient for inclusion)

 -  Woman of childbearing potential must agree to abstain from sexual relations that could
 result in pregnancy or use an effective method of birth control acceptable to both
 participant and study clinician during the study. Men are not required to use
 contraception during the study.

 Exclusion Criteria:

 -  Psychiatric:

 -  Any known diagnosis of a primary psychotic or major neurocognitive disorder,
 including schizophrenia, brief psychotic disorder, or Alzheimer's or other
 dementia, as well as bipolar type I

 -  Severe psychiatric instability or severe situational life crises, including
 evidence of being actively suicidal or homicidal, or any behavior which poses an
 immediate danger to participant or others.

 -  Note: Nonsuicidal depression comorbid with PTSD will not be exclusionary.
 Participants may continue in any concurrent psychotherapy or pharmacotherapy
 in which they are participating, other than pharmacotherapeutic agents
 specifically listed above. Participants with active suicidal ideation or
 with depression severe enough to require psychiatric hospitalization will be
 excluded.

 -  Medical:

 -  Significant bilateral visual loss (would preclude performing the PLR
 measurements)

 -  Current pregnancy or lactation

 -  Allergy or previous adverse reaction to prazosin or other alpha-1 antagonist

 -  Acute or unstable chronic medical illness, including unstable angina, recent
 myocardial infarction (within 6 months), congestive heart failure, preexisting
 hypotension (systolic <110) or orthostatic hypotension (systolic drop > 20mmHg
 after two minutes standing or any drop accompanied by dizziness); autoimmune
 disorders; insulin-dependent diabetes

 -  Chronic renal or hepatic failure, acute pancreatitis, Meniere's disease, benign
 positional vertigo, or narcolepsy

 -  Medication / treatment:

 -  Any use within the 7 days prior to baseline of prazosin, doxazosin, clonidine,
 guanfacine, trazodone, or nonbenzodiazepine hypnotics, and/or unwillingness to
 avoid these medications for the duration of the study

 -  Use of avanafil (Stendra), sildenafil (Viagra), tadalafil (Cialis), and
 vardenafil (Levitra) will be not be permitted during the study dose titration
 period because of increased risk of hypotension in combination with alpha-1
 blockers, but will be allowed at 1/2 the usual starting dose following dose
 titration

 -  Current use of nitrates, or of alternative medications or supplements with
 significant vasodilatory properties (e.g., nitrate containing supplements)
 Participants may also be excluded at the discretion of PI or study clinicians if
 they appear to be unsuitable for this research study for a reason not detailed
 here.