This article is from the WebMD Feature Archive

Just can't get to sleep? Can't stay asleep? Waking up too early? Not feeling refreshed and restored in the morning? Not functioning well during the day? You may have insomniainsomnia.

Up to about one-third of the population have symptoms of insomnia. Those with insomnia typically experience:

• Sleepiness
• FatigueFatigue
• Poor concentration
• Decreased alertness and performance
• Muscle aches
• DepressionDepression during the day and night
• An over-emotional state (tense, worried, irritable, and depressed)

While it may be very difficult to get to sleep at bedtime, you find yourself "out like a light" in front of the TV, at a movie, reading, or even driving. And anticipating getting a poor night's sleep as well as developing rituals and behaviors you think will help your sleep (going to bed earlier) may actually have the opposite effect -- and make the problem worse. Such is the plight, misery, and danger of insomnia.

Many of us experience temporary insomnia from a few days to a few weeks. This kind of insomnia usually results from normal events in our lives such as:

• A stressful event
• Emotional stress
• Illness
• Temporary pain
• Disturbances in sleep hygiene (environmental factors under your control that may contribute to disturbed sleep and insomnia)
• Disruptions to circadian rhythm (the 24-hour rhythmic regulation of our body processes)

When stressful situations resolve, when you recover from illness, when the pain goes away, when sleep hygiene improves -- then sleep usually improves.

Circadian rhythm disruptions like shift work and jet lag may contribute to insomnia because the times you fall asleep and wake up are temporarily shifted. Proper sleep hygiene, particularly the amount of and timing of light, can help re-set your circadian rhythm and improve the symptoms of insomnia from these causes.

Medical Causes

Insomnia also may result from a variety of medical conditions, pain, and even the treatments for these disorders. And poor sleep hygiene can make these medical conditions worse.

Depressive illnesses are almost always associated with sleep disturbances. Those suffering from anxiety may be unable to sleep due to intrusive thoughts, an inability to relax, obsessive worrying, and an "overactive" mind. Bipolar, panic, and psychiatric disorders are each associated with sleep disturbances as well.

Pain from arthritisarthritis, other rheumatologic diseases, cancer, and various neurological disorders, like neuropathyneuropathy from diabetesdiabetes are common causes of insomnia. Gastrointestinal disorders like acid refluxacid reflux and stomach ulcers, as well as angina from heart diseaseheart disease may cause chest pain, and consequent awakenings during the night. In addition, cluster headaches may be precipitated during certain stages of sleep or occur from lack of sleep.

Treatment for these types of insomnia rests primarily with treating the underlying medical condition. These conditions, as with many others, interact with sleep in a complex manner, with each impacting the other. Exactly how all these factors interact is not completely known, but being aware of the sleep component allows us to target each aspect individually and achieve vastly improved interventions and treatments. So it is critical to understand and communicate to your doctor how your condition affects your sleep and that your sleep disturbances may exacerbate your medical condition. This will ensure that he/she may integrate your sleep problem into the overall treatment plan, and utilize a sleep specialist, if needed.

The "pins and needles," "internal itch," or "creeping, crawling sensation" of restless leg syndromerestless leg syndrome (RLS) also make it quite difficult to fall asleep, especially since those symptoms occur more often when one is sleepy or lying down and are relieved only by vigorously moving the legs. The symptoms of RLS may awaken one out of sleep, forcing the sufferer to walk around to relieve the discomfort.

Most people with RLS also have periodic limb movement disorderperiodic limb movement disorder (PLMD), repetitive movements of the toe, foot, and sometimes knee and hip during sleep. These movements may cause arousals that lead to non-restorative sleep. Your doctor can prescribe various medications to reduce or eliminate the movements and the associated sleep disturbances (arousals) caused by these disorders. This results in a more sound sleep, one from which you awaken restored and refreshed.