What causes insomnia?
Lots of different factors can cause you to have trouble sleeping. Short-term insomnia may be caused by stress or a change in your sleeping environment such as noise, bright lights or temperature. Insomnia can also be caused by substances called stimulants that can make it difficult to sleep, such as caffeine, alcohol, nicotine and some medications. Insomnia that lasts longer than a few weeks can be associated with other health conditions including pain, menopause, depression and anxiety disorders, or may be caused by other sleep disorders.