Nightmares in adults: Symptoms, causes, and innovative, science-backed therapies

In a perfect world, sleep offers a respite for body and mind. But for people who experience nightmares, climbing into bed can be like going into battle. Nightmares are most common in childhood, with 25%–30% of children reporting having experienced nightmares in the past month (El Sabbagh, E., et al., Sleep Medicine Reviews, Vol. 71, No. 101834, 2023opens in new window). For many, those bad dreams continue into adulthood. Occasional nightmares are thought to be common in adults, and in a British study with about 800 participants, about 1 in 20 reported having nightmares every week (Rek, S., et al., Social Psychiatry and Psychiatric Epidemiology, Vol. 52, No. 9, 2017opens in new window).

For some people, nightmares cause distress that follows them into their waking lives. Nightmare disorder—defined in the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition, Text Revision) as repeated dreams that are extremely dysphoric, are well remembered, and cause significant distress or impairment in functioning—affects 2%–5% of adults in the general population. A Dutch study of 962 patients with psychiatric diagnoses including mood, anxiety, and personality disorders suggests that the prevalence of nightmares among this population might rise to nearly 30% (Swart, M. L., et al., Psychotherapy and Psychosomatics, Vol. 82, No. 4, 2013opens in new window). Meanwhile, a systematic review indicates that frequent nightmares might affect up to 70% of people with posttraumatic stress disorder (PTSD) (Akkaoui, M. A., et al., Journal of Clinical Medicine, Vol. 9, No. 12, 2020opens in new window).

In people with or without a history of trauma, nightmares can have serious consequences. Disturbing dreams can interfere with healthy sleep, which can lead to downstream problems with emotion regulation and overall mental and physical health. Nightmares can increase anxiety and distress and impair daytime functioning. Research shows they are also associated with an increased risk of suicide.

That link is one important reason that nightmares deserve a fresh look, said Leslie Ellis, PhD, a clinical psychologist in British Columbia who offers courses for clinicians on talking to patients about their dreams and nightmares. Dreams have been of interest to psychologists and psychiatrists since the days of Sigmund Freud and Carl Jung, but that long history can lend “dreamwork” an old-fashioned, unserious air, Ellis said. Yet there is plenty of new research considering nightmares through a more scientific lens. “I think of nightmares as the body’s natural attempt to regulate emotion. And they can indicate that something is serious enough to warrant more attention,” she said.

Despite the significance of nightmares, the public and clinicians alike often fail to recognize the importance of treating them—or even that nightmares can be treated at all. More practitioners would benefit from learning about nightmares and asking patients about them, said William Kelly, PhD, a psychology professor and nightmare researcher at the University of the Incarnate Word in San Antonio, Texas. “Patients don’t always report nightmares if you don’t ask about them, but they could be signaling something important,” he said.

[Related: What is considered a nightmare?]

Nightmares associated with PTSD seem to differ from other nightmares in key ways. Dreams and non-PTSD nightmares occur mostly during rapid eye movement (REM) sleep. PTSD-related nightmares, however, occur across all stages of sleep. They also tend to be more realistic and less fragmented than other dreams. In some cases, nightmares mirror a traumatic event almost exactly, said Deirdre Barrett, PhD, a dream researcher at Harvard University and editor of APA’s journal Dreaming, which published a special section on new research about nightmares in March 2024. Such differences suggest traumatic nightmares may be more akin to flashbacks that occur during sleep, she said. “I think the intrusive memories associated with PTSD are superimposed on every stage of sleep and waking.”

People with frequent non-PTSD nightmares, by contrast, seem less likely to experience the same dream each night, though their nightmares often share similar themes. “Dreams tend to reflect ongoing preoccupations and concerns, sometimes in some bizarre metaphorical ways,” said Antonio Zadra, PhD, a psychology professor at the University of Montreal and a researcher at the Center for Advanced Research in Sleep Medicine. “People might dream of driving off a cliff one night and going down with a sinking ship the next. What’s consistent is a theme of feeling out of control.”

During sleep, the brain is busy stabilizing memories, strengthening them, and integrating them with existing memories, said Robert Stickgold, PhD, a professor of psychiatry at Harvard Medical School who studies the function of sleep and dreams from a cognitive neuroscience perspective. Dreaming allows the brain to discover patterns in all that data, he added. “Dreaming is about trying to figure out what we’ve missed, and nightmares, like other dreams, usually have a waking correlate.”

Research has indicated that both nightmare frequency and severity are associated with higher levels of self-reported worry, depersonalization, paranoia, and hallucinatory experiences (Rek, S., et al., Social Psychiatry and Psychiatric Epidemiology, Vol. 52, No. 9, 2017opens in new window). In general, people whose personality types skew higher on neuroticism and negative affect seem to be most susceptible to nightmares. When they experience stress in their waking lives, it can “flip the switch” that leads to troubled dreams, Kelly said. “When these individuals are sleeping, there’s more activation of fear memories and negative emotion,” he explained.

Other psychologists have theorized that people prone to nightmares may have what are known as “thin” psychological boundaries. “People with thin boundaries tend to experience the world more intensely,” Kelly said. “When [boundaries are] too thin, scary or threatening things can leak over into our dream awareness.”

Kelly’s research centers on trying to understand what drives those frightening dreams. He has found some evidence that difficult experiences from real life can bleed into nightmares. In a study published in the special section on nightmares in Dreaming, he and Hwaheun Kim, PhD, an assistant professor of psychology at California State University, Bakersfield, looked for signs of continuity between a person’s waking experiences and their nightmares. Based on self-reports from a sample of 276 undergraduate students, the researchers focused on nightmares with relational themes such as conflict, loss, betrayal, and rejection. Grief was a particularly strong predictor of relationship-themed nightmares, they found (Dreaming, Vol. 34, No. 1, 2024opens in new window). “This is just a first step. We don’t know yet if people are dreaming about their grief experiences or feared loss,” Kelly said. “But it shows that relational problems [in waking life] tend to show up in sleep.”

In another study in the same special section, Kelly pursued a new theory about why some people may be prone to nightmares. Trying to make sense of the various factors associated with nightmare tendencies, Kelly zeroed in on the concept of concretization—people’s tendency to make abstractions more real or concrete. A person who feels socially anxious, for example, might conclude that people are out to get them, creating a concrete reason in their mind to explain their abstract uneasiness. “The human mind hates ambiguity, especially for something that freaks you out a little bit,” Kelly explained. “Maybe during sleep there’s a corollary where uncomfortable sensations come out through dream imagery.” In a series of studies with 621 university students, Kelly and his colleagues found concretization was strongly related to nightmare proneness, independent of other factors such as neuroticism or trauma symptoms (Dreaming, Vol. 34, No. 1, 2024opens in new window).

Other researchers are working to understand how nightmares affect people during their waking hours. Some people can shake off bad dreams easily, even if they have them relatively often. “Some people even say they enjoy their nightmares—that it’s kind of like going to a horror movie,” said Barrett.

How people respond to nightmares seems to depend in part on what they believe about dreams, according to psychologist Michael Schredl, PhD, head of research at the sleep laboratory at the Central Institute of Mental Health in Mannheim, Germany. He developed a scale to measure beliefs about nightmares and found those beliefs contribute significantly to distress (International Journal of Dream Research, Vol. 12, No. 2, 2019opens in new window). One man who believed dreams could predict the future, for instance, developed intense anxiety after dreaming that he had been shot. Others believe nightmares reveal some kind of hidden psychological problem. “If you believe there’s something bad going on deep down in your mind, it can increase anxiety and distress about nightmares,” Schredl said.

The distress caused by nightmares can be significant. Researchers have documented a link between nightmares and suicide risk in both adults and adolescents, a robust finding that Ellis describes in a review (Journal of Projective Psychology & Mental Health, Vol. 31, No. 2, 2024). Chronic nightmares are associated with an increased risk of suicidal ideation, suicide attempts, and reattempts, and the connection can be dramatic. One study found that in a sample of patients who attempted suicide, frequent nightmares were associated with a fourfold increase in the likelihood of suicide reattempts (Sjöström, N., et al., Psychiatry Research, Vol. 170, No. 2–3, 2009opens in new window).

Long-standing research suggests nightmares can indicate suicide risk independent of trauma or other psychiatric diagnoses (Sjöström, N., et al., Sleep, Vol. 30, No. 1, 2007opens in new window). But a recent study by Westley Youngren, PhD, a psychologist at the University of Missouri–Kansas City who studies sleep and trauma, indicates traumatic nightmares carry the biggest risk. In research published in the special issue of Dreaming (Vol. 34, No. 1, 2024opens in new window), Youngren studied 3,543 veterans with a history of suicide attempts who experienced idiopathic, traumatic, or “complex” nightmares, defined as trauma-related nightmares that coexist with sleep apnea. He found that trauma-related nightmares were predictive of suicide attempts, while idiopathic and complex nightmares were not.

There may be multiple explanations, Youngren said. “Disturbed sleep duration makes us more impulsive and worse at emotional regulation, so that could be playing a role [in suicide risk],” he said. But dream content probably also influences outcomes related to suicide. People with sleep apnea wake frequently during the night because of disordered breathing. As a result of that disturbed sleep architecture and less REM sleep, they may be less likely to remember their dreams—and that may blunt the impact of the disturbing themes and images. People with PTSD who do remember their dreams “have to experience the trauma over and over again,” he said. “It takes away some of that safe haven that sleep provides.”

Unfortunately, standard treatments for PTSD do not necessarily alleviate nightmares, Youngren said—but the reverse appears to be true. “There’s a good amount of research suggesting that treating sleep and nightmares can help trauma-related symptoms overall.”

Though coming as a surprise to many people, research shows that some nightmares can be treatable. People with PTSD are often prescribed a drug called prazosin. Long used to treat high blood pressure, the medication also reduces nightmares in some patients with PTSD-associated nightmares, though studies of its efficacy are somewhat mixed, Youngren said. “And when the medication is stopped, nightmares come back. So, it’s not a long-term treatment,” he added.

Instead, many psychologists have embraced psychological interventions, with the hopes that they will have more staying power. Such interventions include image rehearsal therapy (IRT) and closely related offshoots such as exposure, relaxation, and rescripting therapy (ERRT). Known collectively as “rescripting” therapies, IRT and ERRT involve helping a patient rewrite the narrative in their nightmare to make it less distressing. With a clinician’s help, patients write the new version and review it each day before bed, with the idea that the rescripted story will replace the traumatic nightmare. The goal is not necessarily to give the nightmare a happy ending but to alter the dream enough to make it more tolerable. “A person who saw their friend get killed might rescript it so they’re able to go to their friend and tell him they love him before he died,” Youngren explained.

The American Academy of Sleep Medicine recommends IRT for treating PTSD-associated nightmares and nightmare disorder, while prazosin and other medications “may be used” for PTSD-associated nightmares—a position indicating that the available evidence is less clear (Morgenthaler, T. I., et al., Journal of Clinical Sleep Medicine, Vol. 14, No. 6, 2018opens in new window). “Imagery rehearsal therapies have been used with all kinds of populations, from adult trauma victims to children,” Zadra said. “They are the best tools available at this point, and I think they’ll remain the best tools because they’re effective in a majority of people with nightmares, including trauma-related and [nontraumatic] chronic nightmares.”

While IRT lends itself most easily to recurrent nightmares such as those common in PTSD, it can also benefit people with nontraumatic nightmares. Those with nightmare disorder often have similar themes that show up repeatedly, Zadra noted. Even when nightmares differ from night to night, the act of rescripting them can help people begin to feel they have gained mastery over their dreams. “People feel they’re no longer helpless, and that can lead to different outcomes in future nightmares,” he said. “Next time, you don’t drive off a cliff or get caught by the monster.”

Psychologists can teach patients IRT in three or four sessions, but research suggests even one or two short sessions can have benefits. In a small study conducted during the Covid-19 pandemic, Schredl treated people with nightmares using a single telephone counseling session that included a brief version of IRT. The participants then continued to practice the technique on their own over the following weeks. Schredl found that the single session significantly reduced nightmare frequency in 64% of participants and lessened nightmare distress in 63% (Somnologie, Vol. 25, No. 3, 2021opens in new window).

Still, rescripting therapies are not a slam dunk. A meta-analysis of IRT for posttraumatic nightmares found that the intervention resulted in small to moderate effects on nightmare frequency, sleep quality, and PTSD symptoms (Yücel, D. E., et al., Sleep Medicine Reviews, Vol. 50, No. 101248, 2020opens in new window). “There’s a lot of room to grow. As a researcher, I find it fascinating to ask how we can make IRT better,” Youngren said.

With that in mind, he and his colleagues are exploring a paradigm known as targeted dream incubation. The intervention involves giving people verbal stimuli as they are falling asleep, with the goal of influencing the content in their dreams. Youngren is interested in whether dream incubation could work in concert with IRT, and he is conducting a pilot study to test the feasibility of dream incubation in trauma survivors. “We’ve seen that people who do targeted dream incubation often find they have more control of their dreams. That’s important, since many people who experience nightmares talk about dreams as something that just happens to them, rather than something they can control,” he said.

Other researchers have taken an interest in lucid dreaming. A lucid dream is one in which the person realizes they are asleep and dreaming, a phenomenon movie buffs might recognize from the film Inception. In theory, knowing the monster you are facing is not real could take the edge off a formidable nightmare. Lucid dreaming could work well in concert with IRT to help people gain a sense of control over the events in their dreams, Schredl said. Yet estimates indicate that only about 55% of people experience lucid dreams in their lifetimes, and fewer than a quarter have lucid dreams on at least a monthly basis (Saunders, D. T., et al., Consciousness and Cognition, Vol. 43, 2016opens in new window). Though people can learn to lucid dream, mastering the skill can be difficult. And it is too soon to say how it might help people rewrite the imagery in their nightmares for the better, Schredl said. “Just knowing that you’re dreaming doesn’t necessarily give you the control to change what’s happening,” he said.

While scientists continue to hone interventions for nightmare disorder, they are eager to spread the word that current rescripting treatments do help some people. Those with and without PTSD often have no idea that something can be done about their nightmares, and few even mention their nightmares to health care providers (Nadorff, M. R., et al., Journal of Clinical Sleep Medicine, Vol. 11, No. 7, 2015opens in new window). Many clinicians are equally unaware. “For some time, our views on dreaming have been kind of outdated,” Youngren said. “When a client comes into the clinic, we’re really good at checking to see if they’re anxious or depressed or suicidal, but we still wrongly think of dreaming and nightmares as this other thing that’s not as important.”

That’s not surprising, since clinical training programs typically give scant if any attention to dreams and nightmares. In part, that may be because dreams do not lend themselves easily to research or clinical trials. They happen unpredictably and exist completely inside someone’s unconscious brain. “Nightmares are difficult to trap in a lab,” Kelly said. But that could be changing.

Scientists are applying more cognitive neuroscientific perspectives to dreams and nightmares, and new work on lucid dreaming and targeted dream incubation offers the tantalizing possibility that researchers could probe dreams in real time, Stickgold said. “We’re coming closer to real experimental research on dreaming,” he added. “I believe we’re on the cusp of a real explosion of dream research.”