Insomnia
While insomnia is a common symptom of depression, antidepressants are effective for treating sleep problems whether or not they are associated with depression. While all antidepressants help regulate sleep, some antidepressants such as amitriptyline, doxepin, mirtazapine, and trazodone can have an immediate sedative effect, and are prescribed to treat insomnia. Amitriptyline and doxepin both have antihistaminergic, anticholinergic, and antiadrenergic properties, which contribute to both their therapeutic effects and side effect profiles, while mirtazapine's side effects are primarily antihistaminergic, and trazodone's side-effects are primarily antiadrenergic. Mirtazapine is known to decrease sleep latency (i.e., the time it takes to fall asleep), promoting sleep efficiency and increasing the total amount of sleeping time in people with both depression and insomnia.
Insomnia
Workers who complain of insomnia should not routinely have polysomnography to screen for sleep disorders. This test may be indicated for patients with symptoms in addition to insomnia, including sleep apnea, obesity, a thick neck diameter, or high-risk fullness of the flesh in the oropharynx. Usually, the test is not needed to make a diagnosis, and insomnia especially for working people can often be treated by changing a job schedule to make time for sufficient sleep and by improving sleep hygiene.