Nightmares and sleep

Why are your dreams so vivid lately?

Several things can make dreams more vivid, strange or upsetting: lost sleep, starting or stopping some medicines, quitting cannabis or alcohol, late pregnancy and stress (AASM, 2020; Cleveland Clinic, 2022; Lara-Carrasco et al., 2014; Schierenbeck et al., 2008; Tribl et al., 2013). Many of them change REM sleep, the stage when dreams are usually most vivid (Ebrahim et al., 2013; NINDS, 2025). If a medicine might be behind your dreams, talk to your prescriber, and don’t stop or change it on your own (MedlinePlus, 2026b).

Last updated: 2026-10-13.

What makes a dream feel vivid in the first place?

Dreams are usually most vivid in REM sleep, though they can happen in any stage (National Institute of Neurological Disorders and Stroke [NINDS], 2025). NINDS adds that REM periods get longer as the night goes on.

More REM seems to go with more vivid dreams (Fattal et al., 2023). Among 505 veterans having a sleep study, those whose sleep was more than 25% REM were more than twice as likely to report a vivid dream. That link comes from one group and doesn’t prove that REM causes vividness.

Can losing sleep, or catching up on it, make dreams more intense?

Losing REM sleep can make dreams more dreamlike (Nielsen et al., 2005), and catching up on sleep may make them more vivid. In that sleep-lab study of 27 healthy adults, those whose REM sleep was partly cut short rated their later dreams as more dreamlike. We found no study that tested sleeping in directly. Still, the longest REM periods come late in the night (NINDS, 2025), so sleeping in adds the kind of sleep in which dreams are usually most vivid.

Could a medicine or supplement be behind vivid dreams?

A medicine can change your dreams (Tribl et al., 2013). Their review of 21 studies and 25 case reports found that antidepressants mostly reduce how often people recall dreams. Yet SSRIs and SNRIs, two groups of antidepressants, seemed to intensify dreaming. Stopping them seemed to do so even more. Stopping tricyclics or some MAOIs, two other groups, may cause nightmares. That’s one more reason to talk to your prescriber about any change, and never to stop an antidepressant on your own (MedlinePlus, 2026b).

Other medicines can play a part. Beta-blockers and other medicines for high blood pressure can bring on nightmares, and so can nicotine from smoking or tobacco (American Academy of Sleep Medicine [AASM], 2020; Cleveland Clinic, 2022). Across 39 trials with 10,761 people, varenicline, a stop-smoking medicine, more than doubled the odds of abnormal dreams (odds ratio 2.38; Thomas et al., 2015). In 37 placebo-controlled trials of melatonin, vivid dreams and nightmares were among the possible side effects reported (Besag et al., 2019). If you think a medicine or supplement is changing your dreams, ask your prescriber or pharmacist, and don’t stop, switch or change a dose on your own (MedlinePlus, 2026b).

Why do dreams get so intense after quitting cannabis or alcohol?

Cannabis and alcohol both hold back REM sleep, and REM can rebound afterward (Chan et al., 2013; Schierenbeck et al., 2008). Schierenbeck and colleagues list strange dreams and trouble sleeping among the most consistently reported symptoms of cannabis withdrawal, and sleep studies show a rebound in REM sleep. If quitting is hard, talk to a doctor (MedlinePlus, 2026a).

Alcohol’s effect plays out within a single night (Ebrahim et al., 2013). In their review, alcohol at bedtime delays the first REM period at every dose, usually cuts total REM at moderate and high doses and disrupts the second half of the night. In adults, REM then rises later in that same night, though a lab study of 24 healthy late adolescents, aged 18 to 21, found no such rebound (Chan et al., 2013).

Stopping after drinking often is different. It can be dangerous, and a doctor can help (MedlinePlus, 2025). Nightmares are a common symptom of alcohol withdrawal, which can quickly become life-threatening. If you drank often, recently stopped and think you might be in withdrawal, contact a doctor right away or go to the emergency room. Call 911 or your local emergency number for seizures, fever, severe confusion, hallucinations or an irregular heartbeat.

Does pregnancy change your dreams?

Pregnancy can change dreams, especially in its last months (Lara-Carrasco et al., 2014; Scarpelli et al., 2025). A review of 17 studies found that women tend to have abundant dreams and nightmares while pregnant, often about the pregnancy itself (Scarpelli et al., 2024). In the third trimester, 21% of 57 women expecting their first baby had nightmares more than once a week, against 7% of 59 women who weren’t pregnant (Lara-Carrasco et al., 2014).

Early pregnancy may be different (Scarpelli et al., 2025). In that online study, published in 2025, 100 women in their first trimester reported fewer nightmares than 100 women of the same ages who weren’t pregnant. The authors note that research on the first trimester has been scarce. A dream can’t tell you whether you’re pregnant. A pregnancy test can (NHS, 2022). Nightmares about the baby or the birth are normal, and dreaming something doesn’t mean it will happen (NHS, 2024). If nightmares are disturbing your sleep, the NHS suggests mentioning them to your doctor or midwife.

Can stress or a hard stretch make dreams more vivid?

People under stress or anxiety are more likely to have frightening dreams (NINDS, 2025), and how stress changes your dreams has a guide of its own. If your vivid dreams are of someone you’ve lost, see the guide to dreams about someone who died.

Does cheese before bed really give you strange dreams?

The evidence that cheese gives you strange dreams is weak and self-reported (Nielsen & Powell, 2015). In their survey of Canadian university students, 68 of the 382 who answered (17.8%) said particular foods or eating late at night affected their dreams. Dairy was blamed most, by 43.8% of the students who named a food for disturbing dreams and 38.5% for bizarre ones.

The authors call their results exploratory, since they rest on what students remembered and believed. Two of their four explanations are folklore handed down in families and cultures, and mistaking the cause, such as blaming a pizza eaten before an exam rather than worry about the exam. The other two allow a real effect, from the food itself or from a food intolerance. The only lab study of cheese and dreams they found, run by the British Cheese Board in 2005, was never published in a peer-reviewed journal.

When are vivid dreams a reason to see a doctor?

Some signs that come with vivid dreams call for help:

• You act out dreams, shouting, punching or leaping out of bed. That can cause injury and may point to a sleep disorder, so see a sleep doctor (AASM, 2021).
• Nightmares often wake you and keep you from restful sleep, and you may have come to fear going to sleep. Frequent nightmares like these are considered a sleep disorder, so talk to your doctor (AASM, 2020), and see the guide to nightmares and when to get help.
• The dreams began after you started, stopped or changed a medicine. Talk to your prescriber (MedlinePlus, 2026b).
• You drank often, recently stopped and might be in withdrawal. Contact a doctor right away or go to the emergency room (MedlinePlus, 2025).

Sources

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