A Phase 2 interventional study of Prazosin, ALPRESS® LP 2,5 et 5 mg in Acute Stress Disorder, sponsored by Hospices Civils de Lyon. Completed at 1 site in France. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-05-27.
Sponsored by Hospices Civils de Lyon · Phase 2, Interventional, and Treatment
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.
57 studies on the registry are indexed under Stress Disorders, Traumatic, Acute; 15 are open to participants now.
This study's enrollment of 15 is below the median of 90 across 51 interventional studies indexed under Stress Disorders, Traumatic, Acute.
Browse Stress Disorders, Traumatic, Acute studies →Hospices Civils de Lyon is the lead sponsor of 1,826 studies on the registry; 439 are open to participants now.
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Exclusion Criteria:
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.
PTSD diagnosis
The Presence of PTSD diagnosis will be assessed by the Clinician Administered PTSD Scale (CAPS)
Time frame: 6 months
Acute stress symptoms
These symptoms are assessed by Diagnostic and Statistical Manual of Mental Disorders (DSM V) criteria
Time frame: 14 days
Prazosin side effects
This will be investigated using a self questionnaire about frequent side effects due to Prazosin, measurement of blood pressure, and orthostatic hypotension test
Time frame: 7 days
Prazosin side effects
This will be investigated using a self questionnaire about frequent side effects due to Prazosin, measurement of blood pressure, and orthostatic hypotension test
Time frame: 14 days
Prazosin side effects
This will be investigated using a self questionnaire about frequent side effects due to Prazosin, measurement of blood pressure, and orthostatic hypotension test
Time frame: 1 month
occurrence of complications of PTSD
Complications of PTSD are attempted suicide, suicidal ideation, addiction, depression and quality of life.
Time frame: 6 months
Compliance
Compliance will be evaluated by counting the tablets consumed and not consumed at the end of the treatment by Prazosin
Time frame: 1 month
Plan to share: No
This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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Stress Disorders, Traumatic, Acute→
Hospices Civils de Lyon