Signs and symptoms of insomnia

Signs and symptoms of insomnia

Signs and symptoms of insomnia

Insomnia is effectively both a symptom in itself and a classified sleep disorder (according to the ICSD-3). (8) 

Symptoms and signs of insomnia are typically characterised according to a patient’s expressed difficulty in achieving quality sleep – long periods of time to initiate sleep, frequent awakenings during the night or early morning, and long periods spent awake once awoken.

Insomnia as a disorder is typically characterised as:

  • Difficulty falling asleep, remaining asleep or achieving sleep that is restorative.
  • Sleep difficulty that occurs despite having adequate opportunity to sleep.
  • Sleep difficulty that results in related daytime function impairments and obvious distress.
  • Sleep disturbances that take place at least 3 times a week over a period of no shorter than a month.

In short, a disorder relates to a state or condition whereby a person’s sleep related difficulties correlate with abnormal and negative consequences (pathological responses). (9) 

General signs, symptoms and characteristics of insomnia can be broken down as follows:

  • Difficulties with initiating sleep (falling asleep) even if tired (i.e. lying awake for long periods)
  • Difficulty maintaining sleep
  • Waking during the night and having difficulty falling back to sleep
  • Waking in the early hours of the morning / earlier than desired
  • Sleep that is variable or irregular (e.g. experiencing several nights of poor quality sleep, followed by a full night’s rest)
  • Sleeping for short periods at a time
  • Non-restorative / non-refreshing sleep (i.e. a person may feel like they have not slept)
  • General sleepiness, drowsiness and fatigue during the day (many individuals are more often fatigued than they are actually sleepy during wakeful hours)
  • Memory and concentration problems
  • Forgetfulness
  • Irritability
  • Impaired ability to function normally and perform certain tasks or activities
  • Frequent errors, performance issues, accidents etc.
  • Lack of motivation and focus
  • Lethargy
  • Anxiety and worry relating to sleep
  • Depression
  • Tension headaches

Illustration depicting the counting of sheep.

The signs and symptoms of insomnia impact various aspects of a person’s life. Daily, function, academic or occupational performance, and personal relationships may take a little more strain than normal, particularly for individuals experiencing persistent or chronic insomnia. Risks relating to injurious harm (such as traffic accidents) also increase where chronic fatigue persistently affects a person.

An impaired sense of sleep is also common with individuals battling insomnia. Many a clinical study has determined that individuals who appear sure that they haven’t slept much, had actually achieved a little more sleep than they were aware of during a specific time period. Sometimes a person estimates that it has taken them a longer period of time to fall asleep than testing (a sleep study or monitoring) actually determines.


8. CHEST Journal. November 2014. International Classification of Sleep Disorders-Third Edition [Accessed 04.08.2018]

9. US National Library of Medicine - National Institutes of Health. 15 August 2007. Insomnia: Definition, Prevalence, Etiology, and Consequences: [Accessed 04.08.2018]

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