Mirtazapine: a newer antidepressant.

Mirtazapine is a newer antidepressant that exhibits both noradrenergic and serotonergic activity. It is at least as effective as the older antidepressants for treating mild to severe depression. Sedation is the most common side effect. Although agranulocytosis is the most serious side effect, it is rare (approximately one in 1,000) and usually reversible when the medication is stopped. Mirtazapine is relatively safe in overdose. Many clinicians consider mirtazapine a second-line or even third-line antidepressant to be used when older antidepressants are not tolerated or are ineffective. Physicians who are concerned about the risks of elevated lipid levels and agranulocytosis may choose to reserve mirtazapine as a third-line choice. It is particularly useful in patients who experience sexual side effects from other antidepressants. Mirtazapine is also a good choice in depressed patients with significant anxiety or insomnia. Although mirtazapine has been used successfully in Europe for a number of years, its place in the care of patients with depression in the United States has not yet been established.