You hate alarm clock, you usually need to set it various times to wake up and when you do so, you find it hard to get out of bed and you get up in a bad mood. During day you can’t stop yawning, you feel exhausted and sleepy all day long. Have you found yourself in this description?

There are many people who experience this excessive tiredness during day which is accompanied with sleepiness, a desire to sleep, and a constant fatigue. This feeling of tiredness is known as excessive daytime sleepiness, also known as hypersomnia. It is characterized by constant and involuntary sleep episodes. In other words, a person who suffers from hypersomnia has a great difficulty to stay awake, which is leading to fatigue throughout the day, together with loss of concentration and a decrease of reflexes. These episodes of daytime sleep are increasing during a specific period of time and they often have their highest peaks in situations that imply a low stimulation (in conferences, while reading, watching TV or driving). However, tiredness and lack of concentration and attention also hinder the implementation of activities that require more physical or mental effort.

The American Sleep Association distinguishes 3 levels of intensity of the daytime sleepiness:


  • Mild hypersomnia: the sleepy feeling occurs in monotonous or semi-rest situations: while watching TV, in lectures or conferences, etc.
  • Moderate hypersomnia: occurs when a person performs activities that require a certain level of attention and involvement.
  • Severe hypersomnia: any everyday situation is affected by episodes of intense and uncontrollable sleepiness.


In general, sleep deprivation is the most frequent cause of excessive daytime sleepiness.  This usually happens a lot to students or workers with rotating shift or party time. Other factors that cause tiredness during day may be the following ones:

  • Excessive mental stress: working many hours, having many assignments or demanding many things without having a break to relax and disconnect, all this has its price. Without realizing it, stress makes our muscles tenser, causing exhaustion and is asking for a rest throughout the day.
  • Poor nutrition – having a diet of poor quality, based on fatty foods eventually makes our bodies feel more exhausted by the lack of minerals and vitamins.  Drinking little water is also a determining factor. This factor may be warning of a possible anemia.
  • Emotional factors: Our emotions are reflecting what happens with our body.  A bad experience or too many emotional problems that cause us pain makes us feel under the weather and we only want to sleep.

However, there are times when sleeping as many hours as recommended does not guarantee a good rest. It these cases, the daytime sleepiness or hypersomnia relates with other sleep disorders that are more difficult to discern. Those who suffer from it don’t have trouble sleeping, but sleep does not turn into restorative one.


There are people who manage to reconcile sleep without any difficulty, however, when they wake up, they may feel tired and sleepy during whole day. What happens?

The responsible for this can be a very common sleep disorder: sleep apnea, one of the main causes of hypersomnia. The affected ones, without being aware of it, suffer from apneas or respiratory pauses that interrupt sleep, changing it into one of “poor quality”. This is the explanation of why there are people that even though they sleep enough, but they do not rest.


Narcolepsy is considered the most serious state of hypersomnia. It is characterized by episodes of uncontrolled sleepiness, daydreams and muscle weakness that occur abnormally during vigil. In extreme cases, attacks of involuntary sleep may cause to the affected one a cataplexy (the most distinctive symbol of narcolepsy).

Hypersomnia and narcolepsy share common symptoms, but according to the American Sleep Association (ASA) the difference lies in that “those who suffer from hypersomnia can sleep without difficulty and even much better than most of the people”.

As we have seen, people with hypersomnia have difficulty in getting out of bed in the morning and they feel disoriented during day. Among its symptoms are the following ones: lack of energy, anxiety, irritability, slow thoughts and difficulty in remembering things, loss of concentration and lack of reflection . As a result, the daytime sleepiness is related with the low labor productivity, also affecting the social life of those who suffer from it. In addition, it is estimated that between 15 to 30 per cent of traffic accidents are caused by this disorder. Therefore, before any suspicion or hypersomnia symptom, it is recommended to consult the doctor to make a diagnosis.