The effects of mirtazapine on sleep in patients with major depressive disorder

Mirtazapine is a commonly used antidepressant with a well-known ability to produce sedation. At the same time, its sleep-promoting effects in patients with major depressive disorder (MDD) are relatively unclear. The purpose of this article is to provide clinicians with a detailed review of mirtazapine's sleep effects in patients with MDD.

A literature search was conducted for studies involving mirtazapine in depressed patients that specifically assessed sleep.

Twenty-three studies met selection criteria and were included in this review. Of the 15 studies that included a general assessment of sleep, all noted improvement from baseline with mirtazapine. Twelve of the 23 trials were randomized, blinded, and controlled. Mirtazapine was superior to placebo but did not clearly differentiate itself from other antidepressants, with the exception of venlafaxine. Eight studies used detailed measures of sleep and consistently reported that mirtazapine produced significant improvement in sleep efficiency, total sleep time, and sleep quality. Few investigations combined detailed assessments of sleep along with a comparator antidepressant.

Mirtazapine is an antidepressant with sleep-promoting effects significantly greater than placebo, similar to tricyclic antidepressants, and somewhat similar to selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors. These effects must be balanced with mirtazapine's ability to cause sedation-related side effects.