Dream Hangovers: How and Why Bad Dreams Can Affect You in the Daytime

If your bad dreams affect you the next day, you may be experiencing dream hangovers. Here is what they are and how to avoid them.

Portrait with flare, young man with eyes closed
Getty Images

We’ve all been there: After a night of disturbing dreams or nightmares, you wake up feeling seriously out of sorts. Maybe you feel anxious, tense, queasy, upset, or simply not like your usual self. You may have trouble focusing on what you need to do, or you may feel emotionally depleted after surviving a terrifying ordeal in your dream. Perhaps you’re mad at the person who did you wrong in that dream, whether it was your partner kissing someone else or your boss berating you in front of your colleagues. This sensation is a bad dream hangover, which can make it challenging to get on with your day in the right frame of mind.

Dream hangovers are due to a simple biological phenomenon. When you have a bad dream, stress hormones are released while you’re asleep; when you wake up, they’re still coursing through your bloodstream — that’s what causes the physiological and psychological after-effects, explains Jeanette Raymond, Ph.D., a clinical psychologist in Los Angeles who often works with clients’ dreams to help them better understand themselves.

“When you’re dreaming, the same areas of the brain are activated that would be if you were nervous, anxious, or scared in your waking life,” Raymond shares. “Physiologically speaking, it’s as if you were actually having the experience.”

In a study in a 2019 issue of the journal Psychophysiology, researchers examined whether nightmares result in changes in physiological arousal during sleep. Using ambulatory polysomnography, they found that while people are having nightmares, the bad dreams are accompanied by increased activation of their autonomic nervous system (known for regulating functions like heart rate, blood pressure, digestion, and sexual arousal). The observed changes included heart rate, heart rate variability, breathing, and skin temperature. These changes also often accompany the body’s fight-or-flight response during stressful real-life events.

What’s more, a study in a 2020 issue of the journal Psychoneuroendocrinology found that the day after people experience nightmares, their cortisol awakening response is elevated, and their mood is decreased, compared to days after they had neutral dreams.

It's a pretty universal experience: Research published in the journal Sleep and Hypnosis found that nearly all of the participants in a 444-person trial exhibited effects from their dreams on their daytime moods. Overall, approximately 18% of dreams affected people’s moods during the day. And those who are introverted or have thin emotional boundaries tended to have a higher frequency of dream effects on their daytime moods.

“It’s remarkable how strong an impact bad dreams or disturbing dreams can have on you during the day,” says Dr. Barry Krakow, a sleep medicine specialist in private practice in Savannah, Georgia, and author of “Sound Sleep, Sound Mind,” explaining that after you’ve had an anxiety-producing dream at night, you’re likely to end up with more anxiety the following day.

And sometimes, having disturbing dreams can make people feel anxious about going to sleep the next night, fearing they’ll pick up where they left off with the bad dreams. This could make it difficult to fall asleep, stay asleep, or have good quality Zzz’s.

The bad-dream recovery plan

What can you do about dream hangovers? Plenty, it turns out. Start by recalling the dream — it helps to write down details about it in a journal or record yourself talking about it on your phone — as soon as you wake up. Try to remember as much as you can about the dream and how it made you feel, Raymond recommends. Then, she suggests thinking about any ties between the dream and your waking life. What’s going on in your real life that might be illustrated by or related to this dream? What do the dream images remind you of? What are you uneasy about in real life that might be reflected in the dream images? Why do you think you had this dream now?

“Dreams have messages, and sometimes you can get something interesting out of them, especially if you have a recurring dream,” Krakow says. “The message can be as simple as the emotion in the dream. If you were embarrassed in the dream, maybe there’s something in your life that you’re embarrassed about, and you haven’t addressed that in a healthy way.”

For example, when other people are acting badly toward you in your dreams, this could reflect feelings of mistrust or negativity you have toward them or your relationship. If someone is nasty, deceitful, or behaves in a way that makes you feel uncomfortable in the dream, it may represent “a part of you that is struggling within the relationship and isn’t fully available in real life,” Raymond says.

On the other hand, it could also say something about you or how you feel about certain parts of yourself. “Self-censorship often comes out in dreams as other people doing the bad things — where you project your disowned, unapproved parts onto others,” Raymond explains. In that case, the dream may provide a wake-up call that it’s time to acknowledge and integrate these less desirable but all-too-human parts of you into your sense of self.

How to calm yourself before bed to reduce bad dreams

If distressing dreams frequently take a toll on your mood and your daytime functioning, it’s worth taking steps to calm your mind and body — perhaps by meditating or engaging in deep breathing exercises — before turning in for the night. You also may benefit from trying a technique called imagery rehearsal therapy (IRT), which you can do on your own. In short, IRT has you select a bad or upsetting dream, change the narrative or outcome in some way, then rehearse the new dream you’ve created in your mind during the day, Krakow explains.

Research has found that doing IRT decreased nightmare frequency and symptoms of post-traumatic stress disorder (PTSD) and improved sleep quality among women who’d been sexually assaulted. Another study found that doing IRT decreased the frequency and intensity of nightmares and fear of sleep among combat veterans.

Taking these steps may help you take back the quality of your nights — and set yourself up to feel and function better during the day. But if your bad dreams are frequent, intensely distressing, or have a significant impact on your day-to-day life, consider seeking help from a sleep specialist, Krakow advises. Frequent nightmares sometimes signal an underlying physiological sleep disorder, such as sleep apnea, that can be treated.