Medically reviewed by
Dacelin St Martin, MD
Triple board-certified in Sleep Medicine,
Internal Medicine, and Pediatrics.
The Sleep Cycle | Reasons You Wake Up at Night | How to Sleep Through The Night | When to See a Doctor
Night after night, you find yourself waking up at the same time. You look at the clock, and voila, the magically recurring time: 3 am.
You’re not in this alone. Virtually everyone wakes up in the middle of the night once in a while, but it can be disturbing when this frequently happens.
According to sleep specialists, night awakening is one of the most common sleep complaints.
Many things can cause you to wake up at night. Understanding the sleep cycle is crucial to identifying the cause of your night awakening.
The Sleep Cycle
According to the American Academy of Sleep Medicine (AASM), sleep occurs in four stages.
The first three stages are non-rapid eye movement (NREM) sleep, while the last stage is rapid eye movement (REM) sleep. Every time you sleep, you cyclically go through these stages. In a typical 7-9 hours of sleep, you go through the sleep cycle 4-6 times.
Sleep Cycle Stages:
- Transitional Sleep/Light: It’s the first stage of sleep. It lasts about 1-5 minutes. You start dozing off at this stage, and there is a reduction in the brain and muscle activity.
- Light Sleep: It typically lasts 10-25 minutes per cycle. Your body prepares for deep sleep, and you are easily arousable at this stage.
- Deep Sleep: This stage is crucial to your health because your body repairs itself during deep sleep. It lasts about 20-40 minutes.
- Rapid Eye Movement (REM) Sleep: The brain is very active at this stage, and you may have dreams, typically lasting about 10 minutes.
Reasons You Wake Up at Night
Many things can cause you to wake up at night, and it is not usually problematic if you can fall back to sleep. However, if you wake up at night repeatedly and find it hard to fall back to sleep, it can indicate a problem with your health.
Reasons you wake up at night:
- Anxiety: Anxiety activates your sympathetic system. This system is responsible for alertness, flight, and fight response to danger. Stress can also trigger this system, shifting you from sleep to wakefulness.
- Insomnia: Insomnia is a sleep condition that makes it challenging to initiate and maintain sleep. About 10-20 percent of the general population are estimated to have insomnia. Anyone with insomnia may also complain of early awakening and difficulty falling asleep after waking up.
- Aging: Age heavily influences your sleep cycle, which changes as you get older. Also, you spend less time in deep sleep as you get older, lowering the quality of your sleep. As a result, external elements, such as noise and light, are more likely to wake you up. Your sleep-wake cycles may also change as you become older. You might be able to go to bed and wake up sooner than you did when you were younger. If you have insomnia or an irregular sleep routine, talk to your doctor about age-related sleep changes.
- Drugs: Some medications can interfere with the sleep cycle. Some medicines that could rouse you from sleep in the middle of the night include:
- Cold medications
- Heart medications like Beta-blockers, clonidine
- Stimulants like amphetamine
- Asthma medication like theophylline 
These drugs cause early awakening by reducing sleep quality and modifying sleep architecture.
- Depression: Mental health troubles like depression can cause early-morning awakening and difficulty initiating and maintaining sleep. If you have a persistent low mood, you should see your mental health doctor as soon as possible. Your sleep should improve when your mental health gets better.
- Sleep Apnea (SA): SA is a medical disorder characterized by breathing difficulty during sleep. It can cause repeated awakening during sleep.
- Restless Legs Syndrome (RLS): RLS is a movement disorder characterized by an impulse to move your legs during periods of inactivity, like sleep, and is eased only temporarily by movement.
- Poor Sleep Hygiene: Sleep hygiene is crucial for quality sleep. Improper sleep hygiene and lifestyle can cause you to wake up early at night repeatedly. Habits that can interfere with sleep include:
How to Sleep Through The Night
It’s more likely than not that your night awakening is due to inappropriate sleep habits. Adopting proper sleeping habits might be all you need to get the quality sleep you want. Good sleep practices that can help you sleep through the night include:
- Have a constant time when you go to bed and wake up. Repeat it every day. It will help your body learn to sleep well.
- Make sure you sleep in a cool, quiet, dark room and comfortable bed.
- Have a bedtime routine that helps you relax. You can listen to relaxing music, have a warm bath, whatever works for you.
- Make sure you’re tired before going to bed, and don’t stay in bed for more than 20 minutes if you can’t sleep; get out of bed and do some activities. You can try sleeping again when you are tired.
- Before going to bed, limit your screen time. Try not to use your phone. Also, turn off the television. Light from these devices stimulates the brain and keeps you awake.
- Avoid consuming caffeine and alcohol close to your bedtime.
- Do not eat heavy or hard-to-digest food at night or go to bed hungry. A light snack, like oatmeal or toast, is perfect for nighttime.
When to See a Doctor
- If you consistently have late-night awakenings.
- If you constantly find it hard to initiate sleep when you wake up at night.
- If you suspect that your late-night awakening is due to a medical or mental health problem.
Waking up late in the night is a common sleep problem. In most cases, it resolves with consistent sleep hygiene practices. However, if you have a persistent late-night awakening, see your doctor as soon as possible.
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