Primary insomnia is difficulty getting to sleep or staying asleep, or having non-refreshing sleep for at least 1 month.

The term primary means that the insomnia is not caused by any known physical or mental condition.

Insomnia is caused by many different things. Anxiety, stress, coffee, and alcohol are the most common causes of insomnia.

About 25% of elderly people and about 10% of the general population have insomnia.

Secondary insomnia is insomnia caused by a underlying medical condition. Depression is a very common cause of secondary insomnia. Often, insomnia is the symptom for which people with depression seek medical attention.

See also: Insomnia concerns

• Difficulty falling asleep 
• Waking up several times during sleep
• Fatigue

People who have primary insomnia tend to be preoccupied with getting enough sleep. The more they try to sleep, the greater the sense of frustration and distress, and the more difficult sleep becomes.

The health care provider will perform a physical exam. Questions regarding current medications, recreational drug use, and medical history will be asked. Usually, these are the only methods needed to make a diagnosis of insomnia.

Polysomnography, an overnight sleep study, can help rule out other types of sleep disorders (such as sleep apnea).

The following tips can help improve sleep. This is called sleep hygiene.

• Use the bed only for sleep and sex
• Go to bed at the same time every night
• No daytime napping
• No caffeine, alcohol, or nicotine
• Eliminate the conditioned anxiety that comes with trying to sleep by reassuring yourself that you will sleep or distracting yourself
• Maintain comfortable sleeping conditions
• Eat at regular times daily (avoiding large meals near bedtime)
• Exercise early in the day
• Get out of bed if you are not asleep after 5-10 minutes and doing something else (going to another room may help reduce anxiety about falling asleep)
• Practice evening relaxation routines such as muscle relaxation or meditation

If the above recommendations are followed and the person continues to have insomnia, medications, including benzodiazepines, may be prescribed.

The prognosis is very good if the person sticks to the behavioral maneuvers (sleep hygiene). A doctor should evaluate chronic insomnia that does not improve.

It is important to remember that one's health is not at risk if one does not get 6 to 8 hours of sleep every day and that different people have different natural sleep requirements.

Some do fine on 4 hours a night, while others only thrive if they get 10-11 hours. Sleep requirements also change with age. Listen to your body's sleep signals and don't try to sleep more or less than is refreshing for you.

Daytime sleepiness is the most common complication, though there is some evidence that lack of sleep can also lower your immune system's ability to fight infections. Sleep deprivation is also a common cause of auto accidents -- if you are driving and feel sleepy, take a break.

Call your doctor if chronic insomnia has become a problem.

Goetz, CG. Textbook of Clinical Neurology. 2nd ed. St. Louis, Mo: WB Saunders; 2003: 1207-1210.

Rakel P, ed. Conn's Current Therapy 2005. 57th ed. Philadelphia, Pa: WB Saunders; 2005:34-39.