Abstract
Objective
To provide a clinical update on the treatment of night-time symptoms of posttraumatic stress disorder (PTSD) with prazosin, which is a centrally acting alpha-1 adrenergic receptor antagonist.
Methods
We performed a narrative review of the relevant literature and Clinical Practice Guidelines pertaining to treatment of trauma-related nightmares and insomnia with prazosin.
Results
There is a high degree of heterogeneity among the limited clinical trials to date. However, the most recent systematic review and meta-analysis supports the use of prazosin for suitable patients with PTSD-related nightmares and insomnia. Prazosin is generally well tolerated but patients may experience first-dose hypotension, orthostatic hypotension, or syncope among other side effects.
Conclusion
Although the evidence is very mixed, prazosin may be considered for a targeted time-limited trial in patients whose PTSD is dominated by nightmares and insomnia, who are unresponsive to first-line treatment with trauma-focused psychotherapy and/or evidence-based pharmacotherapies such as antidepressants, and after excluding treatable conditions like obstructive sleep apnoea. The trial should ensure that an adequate dose is used for an adequate duration (if tolerated) with monitoring of blood pressure and any emergent side effects as well as sleep-targeted benefits.
“The night is the hardest time to be alive and 4am knows all my secrets.” ― William J. Martin (formerly quoted as Poppy Z. Brite)
Posttraumatic stress disorder (PTSD) is a distressing and disabling psychiatric condition which is associated with substantial functional impairment, psychiatric and drug and alcohol comorbidities, and increased mortality risk.1–3 The estimated lifetime prevalence of PTSD in the general population of Australia is 11% (14% for women; 8% for men), based on the National Study of Mental Health and Wellbeing 2020–2022. 4
Sleep disturbance represents one of the most pervasive and treatment-resistant symptom clusters in PTSD, with approximately 50–70% of affected individuals experiencing comorbid sleep disorders such as obstructive sleep apnoea (OSA), periodic limb movement disorder, or rapid eye movement sleep behaviour disorder.3,5 Night-time symptoms, particularly trauma-related nightmares and insomnia, but also distressed awakenings, nocturnal panic attacks, and night terrors, are among the most characteristic and distressing features of PTSD. Recurrent nightmares occur in up to 70% of patients and have been linked to poorer sleep quality, elevated depression rates, and heightened suicide risk.3,6 Insomnia (especially initial- and mid-insomnia) is also highly prevalent, affecting up to 90% of individuals with PTSD, and contributes to reduced daytime functioning and increased physical health burden, including poor cardiovascular health, reduced immune function, pain and fatigue.3,5 Importantly, addressing comorbid sleep disorders such as OSA may improve both insomnia and daytime PTSD symptoms. 7
For many patients, these night-time symptoms persist despite adequate treatment of global PTSD symptomatology, indicating the need for targeted interventions. Psychological approaches such as cognitive behavioural therapy (CBT), progressive muscle relaxation, hypnosis, and eye movement desensitisation and reprocessing (EMDR) can improve sleep-related symptoms.8,9 Specific CBT-based strategies include sleep dynamic therapy, lucid dreaming therapy, systematic desensitisation, exposure-relaxation-rescripting, and image rehearsal therapy (IRT) – the latter receiving a level-A recommendation from the American Academy of Sleep Medicine (AASM) for the treatment of PTSD-related nightmares. 8
Given the centrality, severity, and persistence of nightmares and insomnia in many individuals with PTSD, there is a strong clinical rationale for evaluating pharmacological agents that directly target these night-time symptoms. Prazosin has emerged as one such option and is the focus of this clinical update.
Summary of the evidence for prazosin as a treatment for PTSD night-time symptoms
Prazosin has been used for night-time symptoms of PTSD for over two decades, either as a first-line treatment or when other treatments have failed.10–12 It is a centrally acting alpha 1-adrenergic receptor antagonist that counteracts noradrenergic stimulation, thereby potentially reducing the startle response and primitive fear response. 11 This medication was originally introduced in the 1970s for the treatment of hypertension and urinary outflow obstruction caused by benign prostatic hypertrophy.
Prazosin was subsequently proposed as a treatment for hypothesized adrenergic hyperstimulation underlying PTSD-related insomnia and nightmares. Initially (2003–2014), randomized controlled trials (RCTs) demonstrated large effect sizes for improvement in PTSD-related nightmares and insomnia, prompting clinical use. A meta-analysis of the six RCTs evaluating the efficacy of prazosin in treating PTSD-related night-time symptoms was published by Kharchatryan et al. in 2016. 10 This revealed medium-to-large effect sizes. However, the sample sizes of these RCTs were relatively small (20 – 100) and the populations studied were predominantly male veterans, with only two RCTs including civilians. In contrast, the largest RCT to date by Raskind et al. in 2018 revealed negative findings with no statistically significant difference between prazosin and placebo in the relief of PTSD-related distressing dreams or improvement in sleep quality. 13 The sample, which comprised predominantly male veterans, was much larger (n = 304) than any of the previous RCTs, and in fact was greater than the total numbers of subjects in all of the earlier RCTs combined. Following the 2018 Raskind et al. study, AASM downgraded its recommendation for the use of prazosin for PTSD night-time symptoms in a position paper. 9
Zhang et al. performed a systematic review and meta-analysis of the efficacy of prazosin for PTSD night-time symptoms evaluating all RCTs to date in 2020. 11 The authors demonstrated a statistically significant improvement in nightmares (standardized mean difference [SMD] = −1.13, 95%; 95% CI = −1.91 to −0.36), but there was no statistically significant difference between prazosin and placebo for sleep quality and overall PTSD symptoms. Regarding overall acceptability, there was no significant difference between the prazosin and placebo groups with respect to discontinuation for all causes (odds ratio = 1.00, 95% CI = 0.62-1.62).
The evidence for the use of prazosin for PTSD-related night-time symptoms and the generalisability of the research findings for clinical practice is limited due to significant heterogeneity between studies in terms of study populations and study size. This heterogeneity has prompted closer examination of factors that may moderate treatment response and help identify subgroups most likely to benefit. Some putative predictor variables which have been considered to possibly have a bearing on prazosin efficacy include: gender; civilian versus combat veteran status; prazosin dose; duration of treatment with prazosin; concurrent medication; and current use of alcohol. 12 Mendes et al. conducted a systematic review and meta-regression analysis (10 RCTs comprising 648 patients) to address this question in 2025. 12 They found that prazosin significantly improved insomnia (SMD = − 0.654, p = .043) and nightmares (SMD = − 0.641, p = .025), but not overall PTSD symptoms (SMD = − 0.428, p = .077). The meta-regression analysis showed that none of the putative variables were predictors of prazosin efficacy except concurrent medication. Higher benzodiazepine coadministration was associated with greater improvement in insomnia (β = − 0.046; p = .01). The authors considered exploring whether baseline standing blood pressure (as a possible biomarker of a hyperadrenergic state) is a predictor of prazosin efficacy as part of their meta-regression analysis. However, there were no significant differences in baseline blood pressure readings in the four RCTs which provided these data in both the prazosin and placebo groups, and therefore this analysis was not possible to be carried out.
Clinical practice guidelines: Indications for treatment of PTSD night-time symptoms with prazosin
NICE/NHS: National Institute for Health and Care Excellence/National Health Service.
APA: American Psychological Association.
VA/DoD: Department of Veterans Affairs (VA)/Department of Defence.
RANZCP: Royal Australian and New Zealand College of Psychiatrists.
RACGP: Royal Australian College of General Practitioners.
CBT-I: Cognitive Behavioural Therapy for Insomnia.
IRT: Image Rehearsal Therapy.
EMDR: Eye Movement Desensitisation and Reprocessing.
Despite this variability in guideline recommendations, prescribing practices in real-world clinical settings appear more consistent. A relatively recent survey of Australian and New Zealand psychiatrists showed that the most frequently used guideline for PTSD management was over 10 years old and used by less than half (48%) of respondents. 21 Peer-reviewed scientific journals were the most common additional source used by psychiatrists to inform their clinical practice. For the targeted treatment of PTSD-related nightmares 86% of psychiatrists reported having prescribed prazosin, with only 2% indicating that they found it ineffective in decreasing nightmare frequency and/or intensity, despite negative findings in a large RCT.
Practical suggestions regarding treatment of night-time PTSD symptoms with prazosin
OSA = Obstructive Sleep Apnoea.
REM-BD = Rapid Eye Movement Sleep Behaviour Disorder.
SSRI = Selective Serotonin Reuptake Inhibitor.
SNRI = Serotonin and Noradrenaline Reuptake Inhibitor.
aSome studies have found responses within 1–3 weeks of reaching the target dose, but others have demonstrated no response until between 4 and 8 weeks. 10 The Mendes et al. 12 meta-regression analysis found no association between either prazosin dose or prazosin duration, and efficacy – the authors of that paper suggested that this might imply that prazosin’s therapeutic effects are achieved relatively rapidly indicating a possible ceiling effect.
Given that important gaps in the evidence base remain, there is a need for further methodologically robust research into the use of prazosin for PTSD night-time symptoms, including prospective clinical trials with large sample sizes examining specific population groups and predictors of efficacy. Further comprehensive research into the aetiopathogenesis and treatment of insomnia and sleep disorders in PTSD, including nightmares, is needed to address these troubling and debilitating symptoms.
A limitation of this paper is that a narrative review was employed rather than a systematic review. However, the narrative approach allowed for a clinically focused synthesis of key trials, meta-analyses (including a 2025 meta-analysis), and clinical guideline recommendations relevant to everyday practice.
Conclusion
The cornerstone of PTSD treatment remains trauma-focused psychotherapy and evidence-based pharmacotherapy, especially antidepressants. In clinical practice, individuals with PTSD may opt for psychotherapy, pharmacotherapy, or a combination of both, while some may choose to decline these options altogether. In this context, it is valuable to be able to offer a range of treatment approaches tailored to individual needs and preferences. For instance, a person experiencing distressing nightmares may choose symptomatic treatments such as image rehearsal therapy, or prazosin, or both.
Although the evidence is very mixed, given that a very recent meta-analysis demonstrated a medium to large treatment effect size for nightmares and insomnia, prazosin may be considered for a targeted time-limited trial in patients with significant nightmares and insomnia arising from PTSD. Such a trial involves the use of an adequate dose for an adequate duration with monitoring of blood pressure and sleep-targeted benefits (see Table 2). If effective, prazosin may be continued as an ongoing treatment; however, there are currently no evidence-based guidelines specifying the optimal duration of therapy for PTSD.
Based on the most recent evidence for people with PTSD, prazosin may relieve insomnia and nightmares. As more research uncovers further evidence, perhaps newer and more effectively targeted treatments will become available.
Footnotes
Ethical considerations
No ethics approval or consent was required as this paper does not involve research with humans or animals.
Author contributions
All authors have satisfied: Substantial contributions to the conception or design of the work; or the acquisition, analysis or interpretation of data for the work; AND Drafting the work or revising it critically for important intellectual content; AND Final approval of the version to be published; and agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Funding
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Declaration of conflicting interests
The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: PAM, TB, SA, FAW and JCLL are editorial team members for the journal and were not involved in editorial assessment or peer-review of the paper. This paper was independently peer-reviewed.
Data Availability Statement
Data sharing is not applicable as no new data were generated or analysed during this study.
