Insomnia, also known as sleeplessness, is a sleep disorder in which people have trouble sleeping. They may have difficulty falling asleep, or staying asleep as long as desired. Insomnia is typically followed by daytime sleepiness, low energy, irritability, and a depressed mood.

It may result in an increased risk of motor vehicle collisions, as well as problems focusing and learning. Insomnia can be short term, lasting for days or weeks, or long term, lasting more than a month.

Acute insomnia lasts from 1 night to a few weeks. Insomnia is chronic when it happens at least 3 nights a week for 3 months or more.

If it’s hard for you to do everyday activities because you’re tired, your doctor may prescribe sleeping pills for a short time. Medicines that work quickly but briefly can help you avoid problems like drowsiness the next day.

For chronic insomnia, you’ll need treatment for the conditions or health problems that are keeping you awake. Your doctor might also suggest behavioral therapy. This can help you change the things you do that make insomnia worse and learn what you can do to promote sleep.