Teen sleep: Why is your teen so tired?

Teens are notorious for staying up late at night and being hard to rouse in the morning. Your teen is probably no exception. But it's not necessarily because he or she is lazy or contrary. This behavior pattern actually has a physical cause. And there are ways to help mesh your teen's sleep schedule with that of the rest of the world.

Too little sleep

Most teens need about nine hours of sleep a night to maintain optimal daytime alertness. But few actually get that much sleep regularly. Part-time jobs, homework, school activities and friends often are prioritized higher than is sleep. In fact, more than 25 percent of teens report sleeping only 6 1/2 hours a night or less, according to the National Sleep Foundation.

Big deal? Yes. Irritability aside, sleep deprivation can have serious consequences. Daytime sleepiness makes it difficult to concentrate and learn, or even stay awake in class. Too little sleep may contribute to mood swings and behavioral problems. And sleepy teens who get behind the wheel may cause serious — even deadly — accidents.

Is it something else?

In some cases, excessive daytime sleepiness can be a sign of something more than a problem with your teen's internal clock. Other problems can include:

• Medication side effects. Many medications — including over-the-counter cold and allergy medications and prescription medications to treat depression and attention-deficit/hyperactivity disorder — can affect sleep.
• Depression. Sleeping too much or too little is a common sign of depression.
• Sleep apnea. When throat muscles fall slack during sleep, they stop air from moving freely through the nose and windpipe. This can interfere with breathing and disrupt sleep.
• Restless legs syndrome. This condition causes a "creepy" sensation in the legs and an irresistible urge to move the legs, usually shortly after going to bed. The discomfort and movement can interrupt sleep.
• Narcolepsy. Sudden daytime sleep, usually for only short periods of time, can be a sign of narcolepsy. Narcoleptic episodes occur most often after meals, but can occur at any time — even in the middle of a conversation. Sudden attacks of muscle weakness in response to emotions such as laughter, anger or surprise are possible, too.

If you're concerned about your teen's daytime sleepiness or sleep habits, contact your teen's doctor. If your teen is depressed or has a sleep disorder, proper treatment may be the key to a good night's sleep.