Predicting Responses to PTSD Treatment With Iris and Cardiovascular Tests

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. Of note, there is also an additional observational portion of the protocol that is not a direct part of the interventional trial described here, but data from which will be used to help to interpret the data from the interventional trial; because reporting of study results depends on both portiosn, the study completion date estimates/reports will reflect when both the interventional and observational trial components are complete.