Insomnia is a sleep disorder characterized by difficulty falling asleep, staying asleep, frequent awakenings, or waking up too early and being unable to go back to sleep. Insomnia can be short-term (acute) or long-term (chronic).

Insomnia is categorized into three durations: acute or transient if the complaint lasts less than a week; subacute if it lasts between one week and three months; and chronic insomnia if it lasts more than three months.

A widespread disorder worldwide, insomnia affects people of all ages and genders. The causes are variable and depend on the individual, but often stem from factors such as inconsistent sleep schedules, eating before bed, stress-related depression, and alcohol consumption.

Insomnia can lead to various problems in a person's social life and work, causing sufferers to feel physically and mentally unwell. This feeling is a psychological reflection of the insomnia itself.

Difficulty falling asleep at night, frequent interruptions of sleep, waking up early in the morning, reduced energy levels during the day due to sleep deprivation, and an aggressive, tense personality are common symptoms of insomnia.

Insomnia is often treated by adjusting sleep patterns, but if an underlying medical condition is contributing to the insomnia, medication may be recommended.