Monoamine oxidase inhibitors for treatment-resistant depression

Monoamine oxidase inhibitors (MAOIs) constitute the oldest class of antidepressants and are efficacious treatments for patients with unipolar major depression and selected anxiety disorders. Despite being highly effective, the clinical use of MAOIs has been limited by waning clinical experience and a poor understanding of dietary restrictions and drug interactions—to the point that they are now rarely prescribed by most psychiatrists. Nevertheless, there has been renewed interest in the clinical use of MAOIs given the high rates of treatment resistance in people with major depression, the clinical effectiveness of selected irreversible MAOIs for treatment-resistant depressive states, and changes in food preparation techniques and hygiene regulations that have increased the safety of MAOIs. This chapter reviews the clinical pharmacology and efficacy of MAOIs for treatment-resistant depression and provides practical advice on their safe and effective use for this specific indication.