Many teens don't get enough sleep, usually because they're busy and tend to skimp on sleep. But sleep problems can keep some teens awake at night even when they want to sleep.

Over time, those nights of missed sleep (whether they're caused by a sleep disorder or simply not scheduling enough time for the necessary ZZZs) can build into a sleep deficit. People with a sleep deficit are unable to concentrate, study, and work effectively. They can also have emotional problems, like depression.

What Happens During Sleep?

You don't notice it, of course, but while you're asleep, your brain is still active. As people sleep, their brains pass through five stages of sleep. Together, stages 1, 2, 3, 4, and REM (rapid eye movement) sleep make up a sleep cycle. One complete sleep cycle lasts about 90 to 100 minutes. So during an average night's sleep, a person will experience about four or five cycles of sleep.

Stages 1 and 2 are periods of light sleep from which a person can wake up easily. During these stages, eye movements slow down and eventually stop, heart and breathing rates slow down, and body temperature decreases. Stages 3 and 4 are deep sleep stages. It's more difficult to awaken someone during these stages, and when awakened, a person will often feel groggy and confused for a few minutes. Stages 3 and 4 are the most refreshing of the sleep stages — it is this type of sleep that we crave when we are very tired.

The final stage of the sleep cycle is known as REM sleep because of the rapid eye movements that occur during this stage. During REM sleep, other physical changes take place — breathing becomes rapid, the heart beats faster, and the limb muscles don't move. This is the stage of sleep when a person has the most vivid dreams. 

Why Do Teens Have Trouble Sleeping?

Research shows that teens need at least 8½ hours of sleep a night. You don't need to be a math whiz to figure out that if you wake up for school at 6:00 a.m., you'd have to go to bed at 9:00 p.m. to reach the 9-hour mark. Studies have found that many teens have trouble falling asleep that early, though. It's not because they don't want to sleep. It's because their brains naturally work on later schedules and aren't ready for bed.

During adolescence, the body's circadian rhythm (sort of like an internal biological clock) is reset, telling a teen to fall asleep later at night and wake up later in the morning. This change in the circadian rhythm seems to happen because a teen's brain makes the hormone melatonin later at night than the brains of kids and adults do. (Melatonin and another hormone, serotonin, help regulate a person's sleep–wake cycles.)

So, teens have a harder time falling asleep. Sometimes this delay in the sleep–wake cycle is so severe that it affects a person's daily activities. In those cases it's called delayed sleep phase syndrome or "night owl" syndrome.

This isn't the only reason teens lose sleep, though. Lots of people have insomnia — trouble falling or staying asleep. The most common cause of insomnia is stress. But all sorts of things can lead to insomnia, including physical discomfort (the stuffy nose of a cold or the pain of a headache, for example), emotional troubles (like family problems or relationship difficulties), and even an uncomfortable sleeping environment (a room that's too hot, cold, bright, or noisy). Exposing your eyes to excessive light at night — through mobile devices, for instance — also makes it harder to sleep.

It's common for everyone to have insomnia from time to time. But if insomnia lasts for a month or longer with no relief, then doctors call it chronic. Chronic insomnia can be caused by a number of different problems, including medical conditions, mental-health problems, medication side effects, or substance abuse. People with chronic insomnia usually can get help for it from a doctor, therapist, or other counselor.

Worrying about the insomnia can make it even worse for some people. A brief period of insomnia can build into something longer lasting when a person becomes anxious about not sleeping or worried about feeling tired the next day. Doctors call this psychophysiologic insomnia.

Common sleep problems include:

PLMD and RLS

People with periodic limb movement disorder (PLMD) or restless legs syndrome (RLS) find their sleep is disrupted by leg (or, less commonly, arm) movements, leaving them tired or irritable from lack of sleep.

In the case of PLMD, these movements are involuntary twitches or jerks: They're called involuntary because the person isn't consciously controlling them and is often unaware of the movement.

People with RLS actually feel physical sensations in their limbs, such as tingling, itching, cramping, or burning. The only way they can relieve these feelings is by moving their legs or arms to get rid of the discomfort.

Doctors can treat PLMD and RLS. For some people, treating an iron deficiency can make them go away; others might need to take other types of medication.

Obstructive Sleep Apnea

A person with obstructive sleep apnea temporarily stops breathing during sleep because the airway becomes narrowed or blocked. One common cause of obstructive sleep apnea is enlarged tonsils or adenoids (tissues located in the passage that connects the nose and throat). Being overweight or obese also can put someone at risk for it.

People with this sleep disorder may snore, have difficulty breathing, and even sweat heavily during sleep. Because it disrupts sleep, a person may feel extremely sleepy or irritable during the day. People who show signs of obstructive sleep apnea, such as loud snoring or excessive daytime sleepiness, should talk to their doctor.

Reflux

In gastroesophageal reflux disease (GERD), stomach acid moves backward up into the esophagus, producing the uncomfortable, burning sensation known as heartburn. GERD symptoms can be worse when someone is lying down. Even if a person doesn't notice the feelings of heartburn during sleep, the discomfort it causes can still interfere with the sleep cycle.

Nightmares

Most teens have nightmares once in a while. But frequent nightmares can disrupt sleep patterns by waking someone during the night. The most common triggers for more frequent nightmares are emotional, such as stress or anxiety. Other things that can trigger them include certain medicines, and consuming drugs or alcohol. Sleep deprivation (getting too little sleep) also can lead to nightmares.

If nightmares are hurting your sleep, it's a good idea to talk to a parent, doctor, or counselor.

Narcolepsy

People with narcolepsy are often very sleepy during the day and have sleep "attacks" that may make them suddenly fall asleep, lose muscle control, or see vivid dreamlike images while dozing off or waking up. Someone's nighttime sleep may be disrupted, with frequent awakenings throughout the night.

Narcolepsy can be disturbing because people fall asleep without warning, making it hazardous to do things like drive. A person's school, work, or social life can be affected by the unusual sleep patterns.

Narcolepsy isn't common diagnosed in teens, but many cases go unrecognized. People usually first begin to have symptoms between the ages of 10 and 25, but may not be properly diagnosed until 10–15 years later. Doctors usually treat narcolepsy with medicines and lifestyle changes.

Sleepwalking

It's rare for teens to walk in their sleep; most sleepwalkers are kids. Sleepwalking, which may run in families, tends to happen most often when a person is sick, has a fever, is not getting enough sleep, or is feeling stress.

Because most sleepwalkers don't sleepwalk often, it's not usually a serious problem. Sleepwalkers tend to go back to bed on their own and don't usually remember sleepwalking. (Sleepwalking often happens during the deeper sleep that takes place during stages 3 and 4 of the sleep cycle.)

Sometimes, though, a sleepwalker will need help moving around obstacles and getting back to bed. It's also true that waking sleepwalkers can startle them (but it isn't harmful), so try to guide a sleepwalker back to bed gently.

What Should I Do?

If you think you're getting enough rest at night and you're still feeling tired during the day, it's a good idea to visit your doctor. Excessive tiredness can be caused by all sorts of health problems, not just problems with sleep.

If a sleep problem is suspected, your doctor will look at your overall health and sleep habits. In addition to doing a physical examination, the doctor will take your medical history by asking you about any concerns and symptoms you have, your past health, your family's health, any medications you're taking, any allergies you may have, and other issues.

The doctor also might do tests to find out whether any conditions — such as obstructive sleep apnea — might be interfering with your sleep.

Treatment for sleep problems can vary. Some can be treated with medicines, while others can be helped with special techniques like light therapy (where someone sits in front of a lightbox for a certain amount of time each day) or other practices that can help reset a person's body clock.

Doctors also encourage teens to make lifestyle changes that promote good sleeping habits. You probably know that caffeine can keep you awake, but many teens don't realize that texting and using mobile devices, playing video games, or watching TV before sleeping can, too.

Back to Articles

Related Articles

How Can I Stop My Nightmares?

Find out what the experts have to say.

Read More

How Much Sleep Do I Need?

Teens need about 8 to 10 hours of sleep each night. But you might not be getting it. Here's why - and tips for getting more shut-eye.

Read More

What Should I Do If I Can't Sleep?

Find out what the experts have to say.

Read More

5 Ideas for Better Sleep

Insomnia can be a big problem for teens. Read our tips on getting a good night's sleep.

Read More

Stress

There's good stress and bad stress. Find out what's what and learn practical ways to cope in this article.

Read More

Is it OK to Sleep Less on Weekdays and More on Weekends?

Find out what the experts have to say.

Read More

Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.