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.
Flurazepam
Flurazepam is officially indicated for mild to moderate insomnia and as such it is used for short-term treatment of patients with mild to moderate insomnia such as difficulty falling asleep, frequent awakening, early awakenings or a combination of each. Flurazepam is a long-acting benzodiazepine and is sometimes used in patients who have difficulty in maintaining sleep. Flurazepam is still available in the United States. Intermediate half-life benzodiazepines are also useful for patients with difficulty in maintaining sleep (e.g. loprazolam, lormetazepam, temazepam).