Nightmares are dreams that may be disturbing, alarming, or odd. They occur during REM sleep, also known as rapid eye movement sleep. That is the stage when a person’s brain is working hard, almost as hard as when he or she is conscious.
What causes them?
Bad dreams and nightmares are still mysterious to researchers. Even though we don’t have a clue what causes them, there are a lot of things that can make nightmares more likely. Some of them include the following;
Anxiety or stress
The daily stresses of life can bring nightmares. Worrying about school or work can make a person more likely to have one. Bigger events and life changes, such as losing a loved one, can bring nightmares, too.
Mental health conditions
If a person is dealing with conditions like bipolar disorder, depression, general anxiety disorder, or schizophrenia, he or she is more likely to have nightmares. A doctor might suggest things like stress-easing techniques or different types of therapy that can help keep the nightmares to a minimum.
Substance Misuse and Withdrawal
Withdrawal from alcohol or drugs can likewise cause nightmares. For instance, opioid drugs affect parts of the body that regulate sleep. One might have heavy sleep but could also go back and forth between the stages of sleep much quicker. That can bring nightmares. When a person goes through withdrawal and his or her patterns adjust again, the nightmares can persist.
Eating just before bed
A pre-bedtime meal or snack can accelerate metabolism, which can make the brain more active. Try to avoid those after-dinner indulgences.
Scary Books and Movies
Sometimes, reading a scary book or watching a horror movie can cause nightmares, especially if one does them right before bed. Video games and TV shows that scare a person can also make him or her more likely to have a nightmare. Avoid these activities right before you go to sleep.
Nightmares happen at times, but some strategies can cut a person’s chances of having one. Try to:
1. Adhere to a sleep schedule and get enough rest at night.
2. Cut out alcohol, caffeine, and cigarettes.
3. Work out earlier in the day.
4. Relax before you fall asleep.
5. Steer clear of frightening movies, video games, TV shows, and books.
Consult a doctor if the above-mentioned tips do not work.

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REFERENCES
1. Webmd. Causes of nightmares. Available at https://webmd.com
2. Timothy J. (2019). Nightmares. Available at https://healthline.com