Sleep hygiene is the controlling of "all behavioural and environmental factors that precede sleep and may interfere with sleep." It is the practice of following guidelines in an attempt to ensure more restful, effective sleep which can promote daytime alertness and help treat or avoid certain kinds of sleep disorders. Trouble sleeping and daytime sleepiness can be indications of poor sleep hygiene or sleep habits. The International Classification of Sleep Disorders-Revised (ICSD-R) states on page 74: "The importance of assessing the contribution of inadequate sleep hygiene in maintaining a preexisting sleep disturbance cannot be overemphasized." In the ICSD-R, the diagnosis inadequate sleep hygiene is classified as an extrinsic sleep disorder, code 307.41-1.
Doctors and clinicians who advise sleep hygiene strategies for patients and families have lists of suggestions which may include advice about timing of sleep and food intake in relationship to it, exercise, sleeping environment, etc. Which items are suggested for which patients are selected by the clinician, depending on knowledge of the individual situation; the counselling is presented as a form of patient education. Re-education involves a combination of advice about homeostatic, adaptive and circadian aspects of sleep control, how to avoid sleep deprivation, and how to respond to unwanted awakenings from sleep if these occur. As the second edition of the ICSD (ICSD2, 2005) points out, the "sleep disruptive effects of poor sleep hygiene are often obvious to others, but the patients show little insight into this fact."
Recommendations to improve sleep quality include:
- Allowing enough time for sleep. Most people need 7-9 hours of sleep each day.
- Avoiding heavy meals and alcohol before sleep and reducing intake of caffeine and other stimulants several hours before bedtime.
- Arranging a sleep environment that is very dark, comfortable, quiet, and cool to facilitate falling asleep quickly and staying asleep.
- Avoiding TV beds and other media-furniture.
- Following an exercise routine (but not within 3 hours before bedtime), as daily physical activity improves sleep, helps with stress management, and promotes general health.
- Seeking assistance from healthcare providers for continuing difficulties with sleep, since specific sleep disorders may require particular treatments.
Also, some medications cause drowsiness, and in such cases it may be beneficial to use a non-sedating alternative.
See also 
- Van der Heijden, Kristiaan B. et al.: Sleep hygiene and actigraphically evaluated sleep characteristics in children with ADHD and chronic sleep onset insomnia. J. Sleep Res. (2006) 15, 55–62. Retrieved on 2008-06-22
- The International Classification of Sleep Disorders, Revised 2001.
- Tamar Shochat and Sonia Ancoli-Israel (2007). "Sleep hygiene". Nature of Sleep and its Disorders. Armenian Medical Network. Retrieved 2007-09-19.
- International Classification of Sleep Disorders. 2005. ISBN 0-9657220-2-3.
- Running on Empty: Fatigue and Healthcare Professionals: The Consequences of Inadequate Sleep. NIOSH: Workplace Safety and Health, August 2, 2012