Thousands of people with post-traumatic stress disorder have taken the drug prazosin to ease the nightmares and disturbances that stalk their sleep.

Numerous studies have shown the drug to be effective at controlling those episodes. But a team of researchers from the Department of Veterans Affairs, seeking to collect more evidence, set out to study the sustained effectiveness of the treatment. They organized a large, lengthy, multisite trial — the most rigorous type of trial.

The drug was no better than a placebo.


The trial “seemed like a good idea, but you know, live and learn,” said Dr. Murray Raskind, a lead researcher on the trial, which was described Wednesday in the New England Journal of Medicine.

Some researchers not involved with the study were quick to say that clinicians should still prescribe prazosin for some patients; Raskind, director of the VA Northwest Network Mental Illness Research, Education, and Clinical Center, agreed. There are few other treatment options and there is evidence supporting the use of the drug, a generic that was originally approved to treat high blood pressure but is prescribed off label to control nightmares and improve sleep quality in patients with PTSD.

“I don’t think it should change clinical practice — there are six positive studies and one negative study,” said Raskind, who described the research team as “humbled” by the results. He estimated that 15 percent to 20 percent of veterans in the VA system with PTSD are currently prescribed prazosin, and said he did not expect that to change.

But the study has already had some reverberations. Last year, citing the then-unpublished results of the new study, the VA and Department of Defense wrote that there was “insufficient evidence to recommend for or against the use of prazosin as … therapy for nightmares or sleep disturbances associated with PTSD.”

It should be up to clinicians and their patients to decide whether to stop or continue the use of prazosin, the officials said, noting that patients who stop taking it and whose symptoms return might need to restart the therapy.

For some people with PTSD, the trouble isn’t so much getting to sleep, it’s staying that way. Nightmares and other disturbances are common symptoms.

Prazosin is thought to help by blocking the alpha1 receptor for norepinephrine, a chemical that boosts the body’s arousal in response to stimuli. The receptors may become more sensitive in combat settings, which can prove lifesaving there, but “just because you come home doesn’t mean this upregulation of the alpha1 receptor goes away,” Raskind said.

The new study was run over six months at 12 VA medical centers with about 300 participants, half of whom were given a placebo and half of whom were give prazosin. Patients in both arms of the study saw mild improvements in sleep quality and in the frequency and severity of nightmares, but there was no significant difference between the improvements in the different study groups.

Enrollment was limited to people who were clinically stable, meaning they were not drinking heavily, facing family conflicts, or experiencing suicidal or violent thoughts, Raskind said. Because of the long duration of the study, researchers didn’t want to risk exposing such patients to a placebo; some psychiatrists didn’t want their patients enrolled in the study at all for that reason.

But by focusing on stable patients, Raskind and his colleagues may have set themselves up for a negative result, he said. Perhaps, they speculated, only patients experiencing some distress respond to prazosin.

The trial participants had, on average, low blood pressure, which could also help explain why they did not see significant improvement in their sleep. In a separate 2016 study, Raskind and colleagues found that people with high blood pressure were more likely to respond to prazosin, perhaps because higher blood pressure serves as a proxy for how active the adrenaline and arousal system is.

Even though it was a negative trial, the new study still offers insights as researchers try to understand the full complexity of PTSD, said Dr. Matthew Friedman, who led the National Center for PTSD for more than two decades and who was not involved in the new study.

“I really think that we are beginning to recognize that sweeping everything under one PTSD rug may be more than one rug can cover, or should cover,” said Friedman, a psychiatry professor at Dartmouth’s Geisel School of Medicine. “By better defining what the syndrome is that we’re treating, we can better identify medications that could be helpful.”

PTSD was traditionally thought of as an anxiety disorder, but it can also manifest as depression or disassociation or reckless behavior, experts said. The different presentations of the condition that will likely require different treatments.

“I do hope that this trial doesn’t necessarily prevent clinicians from using prazosin as one of the tools in their arsenals,” said Anne Germain, the director of the Military Sleep Tactics and Resilience Research Team at the University of Pittsburgh School of Medicine, who was not involved with the study. “I still think that some people can benefit from it, but we just need to do a much better job of having personalized, predictive treatment algorithms to help people in the end.”

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  • I have PTSD and it has been a big problem in my life, as I essentially can’t have a life. I blow up at people and become abusive, but I can’t bring myself to seek help either, so I’m stuck and going nowhere. A proven drug therapy would compared to the self-medicating I do.

  • I have read many accounts of vets with PTSD who were helped with the herb Kratom, which the FDA is very busily now trying to outlaw.

  • For those of us working in trauma treatment, this is not news, and while there is a place for the placebo argument, it is not with PTSD – a normal response to threatening, overwhelming and abnormal circumstances. It’s a shame when we have approaches like EMDR, which can truly heal the damage from trauma (and not just manage symptoms or put a pharmacological band-aid on it) that so much money is put into things like prazosin instead of directing people toward effective treatment.

  • Many other studies have shown that psychiatric medicines work for those who can tolerate them only because of the placebo effect. Also, many biases seem to operate in drug trials as indicated by the following study: Lancee, M., et al. (2017). Outcome reporting bias in randomized-controlled trials investigating antipsychotic drugs. Translational Psychiatry, 7, e1232].

    We also need to remember that the brain is very complex organ with billions of neurons and trillions of synapses that connect and interact in highly intricate ways – so, simply introducing drugs can mess up the natural biochemical pathways, and adversely affect the functioning of the brain in the long-term. This is what is happening with many psychiatric drugs today (I can provide several references if anyone is interested). On the other hand, practices like mindfulness appear to work very well for conditions like PTSD.

  • Thanks for this article. My husband was started on prazosin after an episode of panic & nightmares while on a road trip in WA in 2012. The excellent ER doc at Aberdeen, in consultation with psychiatry staff, started him on it. He experienced such episodes in the past & it was necessary for me to drive him or have him fly home back to his familiar environment & routine. It may be associated with dementia onset & now with the expensive & controversial addition of Namzaric, he can tolerate such travel & is less irritable. I am a nurse, case manager & now full-time caregiver. This is one drug I would never advise he discontinue.

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