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, somnolency (som'nō-lĕns, -len-sē),
1. An inclination to sleep. Synonym(s): sleepiness
2. A condition of obtusion.
Synonym(s): somnolentia (1)
[L. somnolentia]


Drowsiness, somnolence Sleep disorders Difficulty in maintaining the wakeful state so that the person falls asleep if not actively kept aroused; sleepiness is not simply physical tiredness or listlessness. See Excessive daytime sleepiness.

Patient discussion about sleepiness

Q. I suffer of lack in energy lately, any advice? I’m 35, usually a strong guy but for the past 3 weeks I’ve been sleeping all day, doing nothing while awake, having no energy to do anything. Any one know a reason or what should I do?

A. Have you tried changing your diet? You may lack of vitamins or other essential materials that can cause drowsiness. Try eating vegetables and fruits. Force yourself to do a daily walk, 25 minutes, that’s all. and could be you got an infection that will take some time…

Q. What can cause chronic fatigue? For the last few weeks I’ve been having this strange fatigue, I sleep 12-14 hours at night (I used to sleep 6-7 hours), and I’m tired all day long. It really bothers me. What can is be?

A. Wow, there are so many…to give you a taste- here is a list. I guess some of them you can rule out pretty easily through checking your habits and other symptoms (if you have any):

More discussions about sleepiness
References in periodicals archive ?
Researchers measured the amount of beta-amyloid build-up in their brains over time, and compared those results to the amount of daytime sleepiness each person reported.
Reports do not mention sleepiness as the cause of road accidents, but sudden changing of lanes or swerving in some cases are brought on by sleepiness.
Repeated measures of finger dexterity and sleepiness were done at fixed intervals of 0, 6, 12, 18, and 24 h of SD.
According to the authors, health care providers often dismiss patient complaints of poor sleep and daytime sleepiness during pregnancy.
Asking about any history of safety issues, (8) including sleepiness during driving, cooking, or other activities, is also important.
The use of the scale had been practice beforehand and consisted of the following scores: 1 = extremely alert, 2 = very alert, 3 = alert, 4 = rather alert, 5 = neither alert or sleepy, 6 = some sign of sleepiness, 7 = sleepy, but no effort to stay awake, 8 = sleepy, some effort to stay awake, 9 = very sleepy, great effort to stay awake[13].
The 10% students were defined to have Excessive Day Time Sleepiness (EDS) based on ESS score of >10 and 70.
However, daytime sleepiness, measured subjectively using the Epworth Sleepiness Scale and the Karolinska Sleepiness Scale and measured objectively using the Oxford Sleep Resistance test, did not differ significantly between the two study groups.
Keywords: Sleep quality, Medical student, Excessive daytime sleepiness, Pittsburgh sleep quality index, Epworth sleepiness scale.
Collectively, they contribute to the increase in daytime sleepiness frequently found in PD patients.
The primary objective was to identify at least one dose of E2006 that could provide a satisfactory balance of sleep efficiency (total sleep time as a proportion of time in bed) and next-day residual sleepiness.
Association of Sleep and Fatigue With Decision Regret Among Critical Care Nurses" found that nurses impaired by fatigue, loss of sleep, daytime sleepiness, and an inability to recover between shifts are more likely than well-rested nurses to report decision regret.