It is estimated that between 50-70 million Americans suffer from either chronic sleep loss or a diagnosable sleep disorder with 10% of the population reporting not getting enough sleep to function effectively within any given month. Sleep hypnotics and benzodiazepines are the usual drugs for treating sleep problems but can have the potential to cause addiction and worse insomnia when they are withdrawn. Antidepressants can also be used to treat insomnia but not all antidepressants work in the same way and some can actually damage sleep quality. Joseph M. Holshoe from the University of Alabama reviewed the research into antidepressants and sleep. He found that the sedating tricyclic antidepressants such as amitriptyline, nortriptyline, doxepine and clomipramine all improved sleep quality while the stimulating tricyclics trimipramine, desipramine and protriptyline made it worse. Of the selective serotonin reuptake inhibitors (SSRIs) only escitalopram improved sleep quality; fluoxetine, paroxetine, citalopram, venlafaxine and duloxetine all made it worse. A category of drugs called serotonin-2 receptor antagonists/reuptake inhibtors (SARIs) had more beneficial effects with low doses of trazodone and nefazodone being found to be good treatments for insomnia. The effects of bupropion were unclear. Mirtazapine was found to improve sleep but was associated with day-time sleepiness and weight gain.
Holshoe, Joseph M. - Antidepressants and sleep: a review Perspectives in psychiatric care 45(3), 191-197