What are the causes of insomnia? The American Academy of Sleep Medicine defines insomnia one of two ways in broad categories: either acute, which is less than one month; or chronic, which is greater than one month. And basically you can go and divide the causes of insomnia into three major categories and they are: the predisposing factors, which are things such as depression or anxiety; precipitating factors, which includes stresses in life, changes in job, divorce, shift work that has changed; and last but not least there are perpetuating factors which are the preoccupations or worries about why you aren't sleeping correctly throughout the night. In the American Academy, it is recommended that the first line of the therapy is cognitive behavior therapy and we also sometimes use medical therapy to take care of these disorders, so both combined help to take care of insomnia problems. And these do not happen overnight, nor do they go away overnight.