Prazosin in pregnancy: treating post-traumatic stress disorder in the absence of evidence

Introduction

Post-traumatic stress disorder (PTSD) affects approximately 4–6% of pregnant women and is associated with significant maternal and infant morbidity, including impaired bonding, feeding difficulties, and altered infant cortisol regulation.(1) Prazosin, an alpha-1 adrenoceptor antagonist, is used off-label for trauma-related nightmares and sleep disturbance in PTSD. Despite its clinical use, evidence supporting its safety and efficacy in pregnancy remains critically inadequate. The aim of this review is to synthesise the available literature on prazosin use during pregnancy and lactation, evaluate indirect evidence from non-pregnant PTSD populations, and identify barriers contributing to the persistent evidence gap in perinatal psychopharmacology.

Methods

A narrative literature review was conducted across PubMed, Google Scholar, ResearchGate, and ScienceDirect. Search terms included “prazosin,” “alpha-1 antagonist,” “PTSD,” “pregnancy,” “perinatal,” and “nightmare,” combined using Boolean operators. Inclusion criteria encompassed human studies of all designs examining prazosin use in pregnant or perinatal populations, alongside studies relevant to mechanism, safety, or PTSD treatment. Animal studies and non-retrievable full texts were excluded. Studies were organised thematically into custom reference management folders and key data extracted into a comparative evidence table, forming the basis for synthesis and gap identification.

Results

Direct evidence is confined to a single prospective observational study of 11 pregnancies exposed to prazosin.(2) Reported outcomes included two miscarriages, one case of pre-eclampsia, one postpartum haemorrhage, one preterm birth, and two neonatal intensive care admissions. These rates broadly align with background population frequencies, though significant confounders were present, including smoking in five participants and concurrent psychotropic use in six. A systematic review of prazosin in pregnancy identified no studies examining its use for PTSD specifically, with all available pregnancy data focused on hypertension rather than psychiatric indications. Lactation data derive from a single case; breastmilk excretion was estimated at approximately 3% of the maternal dose, with no published infant level or outcome data identified.(3) In non-pregnant populations, early placebo-controlled trials demonstrated significant reductions in trauma-related nightmares and nocturnal hyperarousal. However, a subsequent multisite randomised controlled trial of 304 military veterans found no significant difference between prazosin and placebo for nightmare frequency or sleep quality.(4) A systematic review and meta-analysis of 40 studies confirmed that untreated maternal PTSD is associated with reduced breastfeeding, feeding and sleeping difficulties, smaller infant head circumference, and lower infant cortisol levels.(5)

Conclusions

The evidence base for prazosin in pregnancy remains inadequate. The absence of consistent harm signals should not be interpreted as evidence of safety; it is simply evidence of absence. Current recommendations rely on indirect data from non-pregnant adults who differ fundamentally in physiology and pharmacokinetics. This reflects systemic barriers including ethical constraints, medico-legal liability, and the historical exclusion of pregnant women from clinical trials. Untreated maternal PTSD carries well-documented risks for both mother and infant, yet pregnant women and prescribers currently lack even basic guidance resources. Emerging platforms including placental organoids and pregnancy-specific pharmacokinetic modelling offer future promise, but remain insufficiently integrated into drug development. Until these barriers are addressed, pregnant women with PTSD will remain without clear guidance.

References

1. Khoramroudi R. J Family Med Prim Care. 2018;7(1):220-3.
2. Zitoun N, et al. Br J Clin Pharmacol. 2023;89(11):3324-9.
3. Prazosin. LactMed®. National Institute of Child Health and Human Development; 2006.
4. Raskind MA, et al. N Engl J Med. 2018;378(6):507-17.
5. Zitoun N, et al. BMC Pregnancy and Childbirth. 2025;25