Snoring
A common symptom of a sleep disorder, snoring can cause significant medical and social problems. It occurs when tissues in the air passages relax and the passage of air causes these tissues to vibrate.

Sleep Apneas
An irregularity in breathing during sleep, sleep apnea can be life threatening. Obstructive sleep apnea generally occurs when the upper airway is blocked by the tongue or palate during sleep, causing breathing difficulties. Central sleep apnea is a complete suspension of breathing. Both can lead to hypertension, cardiac irregularities, heart failure, and stroke.

Narcolepsy
Narcolepsy is a disabling disorder often undiagnosed.  Uncontrollable sleepiness, paralysis, and hallucinations are common symptoms.

Sleep-Wake Schedule Disorders
Circadian disorders are abnormalities in sleep-wake schedules. Of the many causes, the best known are jet lag and shift work.

Excessive Daytime Sleepiness
People with EDS frequently doze, nap, or fall asleep in situations where they need to be or want to be fully awake and alert.

Sleepwalking
Sleepwalking, or somnambulism, is a state in which a person rises from sleep, with little awareness of surroundings, to perform what appear to be conscious motor activities. Although adults may be afflicted, this occurs more frequently in adolescents.

Nocturnal Myoclonus
Nocturnal myoclonus is one of several periodic limb movement disorders. This condition is characterized by sudden repetitive kicking or jerking movements of the lower extremities. This can occur through the night every 20 to 40 seconds.

Nocturnal Asthma
Nocturnal asthma, characterized by an increase in nighttime symptoms, is related to sleep and to bodily circadian rhythms. This is surprisingly common. Patients may awaken with coughing, chest tightness, or wheezing. When this happens nightly, sleep disruption can be extreme.

REM Sleep Behavior Disorders
REM behavior disorder is a sleep disorder associated with REM (or dreaming period) sleep, which includes a violent acting out of one's dreams. Occasionally, while experiencing this, people have caused injury to themselves or others without waking.

Restless Legs Syndrome
Periodic leg movements in sleep are frequently associated with a waking disorder called restless legs syndrome (RLS). RLS is a disorder of the central nervous system that is characterized by unusual sensations in the legs and an overwhelming urge to move the legs while resting or attempting to fall asleep.

Sleep Disorders in the Elderly
More than half of the population over 65 experiences some form of sleep disorder. Factors that can contribute to this are aging, stress, medication, and an underlying medical condition.