Insomnia is a sleep disorder, where people have trouble falling asleep, remaining asleep or both. It may be ongoing (chronic) or short-term (acute), lasting from a few days to years.
Insomnia may be due to psychological issues, medical conditions, hormones, drugs, alcohol or medicines, or disruptions to circadian rhythms. In the psychological research field, insomnia has been linked to anxiety.

People with insomnia have poor quality or too little sleep, which affects ability to concentrate, and can lead to reduced performance at work or school.

Insomnia can also lead to poor immune system functioning, and an increased risk of long-term disease.

Symptoms of insomnia may include:

  • Difficulty in falling asleep
  • Waking during the night
  • Waking early morning
  • Sleepiness during the day
  • Lack of energy
  • Feeling irritable or anxious
  • Headaches
  • Being uncoordinated
  • Difficulty in focusing and concentrating
  • Health problems