About one-third of Americans have symptoms of insomnia but less than 10% of those are identified by their doctors. Insomnia tends to increase with age and affects about 40 percent of women and 30 percent of men. Insomnia includes not only difficulty falling asleep (this is called sleep-onset insomnia) but also waking up to early and not being able to fall back asleep (sleep-maintenance insomnia), frequent awakenings, and waking up feeling unrefreshed.

Symptoms of insomnia include sleepiness, fatigue, decreased alertness, poor concentration, decreased performance, depression during the day and night, muscle aches and an overly emotional state. Temporary insomnia can be brought on by stress, illness, pain, diet, medications and disruptions to circadian rhythms. When symptoms occur more than a few times a week and affect daily functioning, the person should consult a health care provider. Experts say that chronic insomnia is a greater mortality risk than smoking, high blood pressure and heart disease.

Treatment for insomnia can include medication and behavioral strategies. Depending on how severe the case, doctors may prescribe non-benzodiazepine hypnotics, antidepressants and hypnotics. Behavioral strategies are:

• Sleep restriction — only sleeping in the bed and only staying in bed when sleeping (falling asleep within 25 minutes of lying down)
• Stimulus control — reserving the bedroom for sleep and sex only
• Relaxation techniques
• Avoidance of caffeine and alcohol
• Cognitive behavioral therapy with the help of a psychologist.

Types of Insomnia

Sleep onset insomnia

Sleep onset insomnia is when a person can't get to sleep when he or she wants to. In chronic conditions, when the person also has difficulty getting up in the morning, this can be classified as delayed sleep phase syndrome. In this case, the person's clock is just off: when the body wants to sleep is not the same as when the mind wants to sleep.

More frequent and pedestrian sleep onset insomnia is just caused by having a lot on your mind or by being nervous. Anxiety-induced insomnia is also called Psychophysiological Insomnia. This is usually short term. In severe situations, this type of insomnia can often be treated with behavioral therapy. The person learns to relax or meditate or systematically clear the mind.

Sleep Maintenance Insomnia

Sleep maintenance insomnia results in frequent and prolonged nocturnal awakenings, especially in the second half of the night. Many of the new sleep medications introduced in recent decades address sleep maintenance more than falling asleep.

Sleep onset insomnia is more common in young adults while sleep maintenance insomnia is common in the elderly. Delayed sleep phase syndrome usually strikes in adolescence, so it makes sense that young adults are more prone to sleep onset insomnia.

Primary Insomnia

Primary insomnia is sleeplessness that cannot be attributed to some other cause. An estimated 10% of the population has primary insomnia.

A patient with primary insomnia must experience difficulty in falling asleep, difficulty in staying asleep, early awakening, or non-restorative, poor quality sleep. The trouble sleeping must be associated with daytime symptoms. These can include fatigue, trouble concentrating, memory or mood disturbances, tension headaches, and other types of daytime impairments or symptoms.

The pathophysiological mechanisms underlying primary insomnia are usually unknown, and medical practitioners address the insomnia directly. Sleep researchers believe that hyperarousal, circadian dysrhythmia, and homeostatic dysregulation underlie chronic insomnia. But as a practical matter for doctors, patients just want a good night’s sleep.

The first line of attack for primary insomnia is almost always drug-free. Good sleep hygiene is always recommended, and those suffering from sleepless nights are advised to take another look at their bed practices. Often turning down the air temperature in the room is all it takes to facilitate unbroken sleep.

Chronic Insomnia

Chronic insomnia is insomnia that goes on for a month or more – is often considered primary insomnia. Doctors attack insomnia directly (rather than an unknown “underlying cause”) to help the patient achieve a better quality of life.

Secondary Insomnia

Secondary insomnia is a result of other causes – illness, drugs (including caffeine and alcohol), excessive worrying, pain, etc. Depression is a leading cause of secondary insomnia. If the doctor and patient can figure out the underlying condition, treating it is often more productive than attacking the insomnia directly. Many depressives start sleeping much better as soon as they begin taking antidepressant medication, even though those medications have no effect on the sleep patterns of non-depressed people. Pain relief medications often produce drowsiness as a side effect. This is most obvious in the very strong opiate pain medications, and opium has been known for millennia to induce sleep. (Indeed, morphine was named after Morpheus, the god of sleep). Less strong over-the-counter pain medications are often mixed with antihistamines. The strongest example is Tylenol PM, which is a mixture of the pain reliever acetaminophen (the ingredient in regular Tylenol) and diphenhydramine HCl., an antihistamine that promotes sleep.

Opiate medicines such as percodan as well as OTC preparations like Tylenol PM disrupt the sleep cycle to some extent, so they are not suggested for long term treatment of insomnia. But they can effectively address sleeplessness if the patient needs pain relief medication for other reasons.

Secondary insomnia causes include stress, arthritis, and drinking too much coffee. The insomnia is a sequela of another problem. Secondary insomnia is more common than primary insomnia.

Rebound Insomnia

Rebound insomnia is when you can’t sleep after coming off sleeping pills. Your brain and body have adjusted to the sleep medication to some extent and almost anticipate it. The feedback mechanisms have had their set point adjusted, to some extent. This set point changes of course, but in the short run your body experiences insomnia in response to the lack of drug. A related phenomenon is “rebound pain” that people experience when they stop taking pain relievers. Some people experience both rebound pain and rebound insomnia if they have been taking something like Tylenol PM, which contains both a pain reliever and an antihistamine.

Rebound insomnia is very common, and a reason to avoid medication if possible. One way to reduce it is to wean yourself off the drug. Reduce the dosage over a few nights to permit your body to slowly get used to sleeping without the medicine. You can also try other methods of getting to sleep: good sleep hygiene, exercise, warm milk. Even a different type of sleeping pill would probably work, but doctors would almost certainly not recommend using one sleep aid to counteract rebound insomnia caused by stopping a different sleep aid. Consult a doctor if you feel this is the only way.

Altitude Insomnia

You sometimes hear the term “altitude insomnia” when people can’t sleep after climbing a mountain (or flying to a city like Denver.) More properly, there is a condition called Acosta’s syndrome, or hypobaropathy, or altitude sickness, which can have many symptoms, including sleeplessness. Sensitive individuals experience this when they go up as little as 2000 ft in elevation.

While in extreme cases altitude sickness can be serious, most people suffer through the discomfort and adjust in a few days. The no-brainer solution to this sickness is to descend back to the starting elevation, at which point symptoms usually clear rapidly.

Insomnia related to substance use

Substance use refers to alcohol, stimulants, drugs (including sleep aids, both prescription and over the counter.) Substances are often used in tandem, compounding the effect and making identifying the cause of the sleeplessness difficult.

The same substance can have opposite effects on different individuals: caffeine seems to help some people fall asleep while it keeps others up. Poisons can also interrupt sleep and a symptom of low dose poisoning is insomnia. These poisons could include spider venom and lead.

Non-restorative Sleep

Some researchers and psychologists and medical doctors have been using the phrase non-restorative sleep (abbreviated NRS), but this terminology has not been officially adopted by any formal body. It generally means the feeling at waking of not being refreshed. Plenty of people experience it, but it doesn't necessarily mean it fits the clinical definition of a sleep disorder the way difficulty initiating and maintaining sleep (insomnia) does.