Efficacy of Prazosin in Preventing Post-traumatic Stress Disorder (PRAZOSTRESS)

May 22, 2026 updated by: Hospices Civils de Lyon

Preliminary Study About the Efficacy of an α1 Blocker (Prazosin) in Preventing the Occurrence of Post-traumatic Stress Disorder (PTSD) in Patients With Acute Stress

After a traumatic event such as an accident or an assault, victims may experience intense stress symptoms that may evolve into "post-traumatic stress disorder" (PTSD). It is a frequent and serious pathology, which can be complicated by depression, addiction or suicide. Few means are available to prevent PTSD in people who have just undergone trauma. Prazosin is an antihypertensive drug that blocks α1 adrenaline receptors which could help to stop the vicious circle of stress and prevent the development of the disease. The objective of this study is to demonstrate the efficacy of prazosin to prevent PTSD in patients who visit an emergency department after trauma.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
15

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • France
      • Lyon, France, 69003
        • Groupement Hospitalier Edouard Herriot - Emergency Psychiatry Department

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patient of age >18 years and <65 years
  • Victim of direct experience trauma (accident or physical aggression)
  • Presence of an ASD between D3 and D7 after the trauma according to DSM V criteria

Exclusion Criteria:

  • Contra-indication to prazosin: orthostatic hypotension, right heart failure, other hypotensive therapy, 5-phosphodiesterase inhibitors (sildenafil) or diuretic, history of syncope or severe unexplained faintness, hypersensitivity known to quinazolines.
  • Alcohol and / or drug use at the time of the trauma
  • History of psychotic disorder
  • Suicidal risk defined by a score ≥ 2 on the Suicidal Ideas Item of the Beck Depression Inventory (BDI)
  • Protected or vulnerable Major
  • Persistence of a life threatening injury at D3
  • Sexual assault
  • Only moderate head trauma can be included and therefore excluded patients with loss of consciousness greater than 30 minutes, Glasgow score less than 13, post-traumatic amnesia greater than 24 hours (Ruff et al., 2009) .
  • Prescription of morphine or morphine derivative in progress
  • Pregnancy or breastfeeding period
  • Lack of effective contraception in a woman susceptible to childbearing
  • Known hepatic dysfunction
  • Narcolepsy (Gelineau's disease)
  • Cardiac or vascular history including coronary artery disease
  • Strict low-sodium diet

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Prazosin, ALPRESS® LP 2,5 et 5 mg
Patients included in this study will be adults with acute stress as a result of a direct experience traumatic event. They will be treated with Prazosin, ALPRESS® LP 2,5 et 5 mg during 28 days.
Drug: Prazosin, ALPRESS® LP 2,5 et 5 mg

Patients will take Prazosin during 28 days ; there are two periods of treatment (escalation of doses):

  • PERIOD 1 (Day 0 - Day 7): 1 tablet of ALPRESS LP 2.5 mg (Prazosin) at bedtime for 7 days
  • PERIOD 2 (Day 8 - Day 27): 1 morning tablet of ALPRESS LP 5 mg (Prazosin) at bedtime for 21 days.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
PTSD diagnosis
Time Frame: 6 months
The Presence of PTSD diagnosis will be assessed by the Clinician Administered PTSD Scale (CAPS)
6 months

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Acute stress symptoms
Time Frame: 14 days
These symptoms are assessed by Diagnostic and Statistical Manual of Mental Disorders (DSM V) criteria
14 days
Prazosin side effects
Time Frame: 7 days
This will be investigated using a self questionnaire about frequent side effects due to Prazosin, measurement of blood pressure, and orthostatic hypotension test
7 days
Prazosin side effects
Time Frame: 14 days
This will be investigated using a self questionnaire about frequent side effects due to Prazosin, measurement of blood pressure, and orthostatic hypotension test
14 days
Prazosin side effects
Time Frame: 1 month
This will be investigated using a self questionnaire about frequent side effects due to Prazosin, measurement of blood pressure, and orthostatic hypotension test
1 month
occurrence of complications of PTSD
Time Frame: 6 months
Complications of PTSD are attempted suicide, suicidal ideation, addiction, depression and quality of life.
6 months
Compliance
Time Frame: 1 month
Compliance will be evaluated by counting the tablets consumed and not consumed at the end of the treatment by Prazosin
1 month

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Hospices Civils de Lyon

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
April 21, 2017

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 30, 2020

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 30, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
February 2, 2017

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 6, 2017

First Posted (Estimated)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
February 7, 2017

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 27, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 22, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
May 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 69HCL16_0628
  • 2016-004653-32 (EudraCT Number)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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