Last updated: August 15, 2026 · 8 min read Insomnia is one of the most common sleep disorders. It is manifested by challenges falling asleep, staying asleep, or having quality sleep. Insomnia affects even people who have the time and ideal sleeping environments. Short-term insomnia takes place for a few days or weeks but often does not exceed three months. It is usually associated with acute stress, such as grief or a significant illness.