Sleep disorders are characterized by difficulty with falling asleep, staying asleep, or maintaining alertness during the day. There are several different types of sleep disorders. Each may involve one or more of these basic symptoms:
Insomnia sufferers may have difficulty falling asleep, or may awaken early and have trouble getting back to sleep. Many conditions can cause or exacerbate insomnia: stress, pain, chronic disease, or breathing problems. In addition, misuse or overuse of sleep medications may cause or worsen insomnia.
Narcolepsy is characterized by extreme sleepiness during the day. People with narcolepsy may fall asleep unpredictably, or they may suffer attacks of muscle weakness brought on by laughter, joy, anger, or other intense emotion. Sometimes narcoleptics experience frightening dreams or hallucinations as they are falling asleep.
Sleep Apnea can be a serious condition involving breathing patterns during sleep. People with sleep apnea stop breathing periodically while sleeping, sometimes hundreds of times in a single night. These individuals tend to snore and snort loudly during sleep, and may be sleepy during the day. Sleep apnea is the most common cause of daytime sleepiness.
Periodic Movements in sleep (nocturnal myoclonus) and Restless Legs Syndrome are related to abnormal movements or sensations prior to or during sleep. Periodic movements are repetitive leg jerks that occur when the body is at rest or asleep. Sufferers of restless leg syndrome experience severe, uncomfortable sensations in their legs at night, preventing them from falling asleep. Individuals also may complain of insomnia and excessive daytime sleepiness.
In addition to these disorders there are a number of other problems that can occur during sleep, including recurrent nightmares, night terrors, sleep walking, bruxism (teeth grinding), head banging, and seizures. Sufferers may not be aware of these problems until others have observed them.