The American Academy of Sleep Medicine estimates 30% of adults have some symptoms of insomnia, 10% have insomnia symptoms so severe they cause consequences such as daytime sleepiness, and less than 10% have chronic insomnia.
Insomnia may be classified by how long the symptoms are present.
- Transient insomnia usually is due to situational changes such as travel, extreme climate changes, and stressful events. It lasts for less than a week or until the stressful event is resolved.
- Short-term insomnia usually is due to ongoing stressful lifestyle or events, medication side effects or medical conditions and lasts for one to three weeks.
- Chronic insomnia (long-term insomnia) often results from depression, digestive problems, sleep disorders, or substance abuse and continues for more than three weeks.
Transient insomnia may progress to short-term insomnia and without adequate treatment short-term insomnia may become chronic insomnia.
Some of the medications and substances that can contribute to insomnia are:
- caffeine and coffee,
- decongestants (for example, pseudoephedrine),
- diuretics (for example, furosemide [Lasix], hydrochlorothiazide [Dyazide]) especially if taken in the evening or at bedtime,
- antidepressants (for example, bupropion [Wellbutrin, Wellbutrin SR, Wellbutrin XL, Zyban], fluoxetine [Prozac]),
- appetite suppressants (for example, sibutramine [Meridia], phentermine [Fastin]), and
Insomnia also may be the result of withdrawal from:
- benzodiazepines (for example, diazepam [Valium], chlordiazepoxide [Librium], lorazepam [Ativan]),
- marijuana, and
- other addicting drugs.
Insomnia can also result from poor sleep-related habits (poor sleep hygiene).